2-Substituted 1-arylpiperazines as tachykinin antagonists and/or serotonin reuptake inhibitors

ABSTRACT

The present invention relates to piperazine derivatives of formula (I), wherein R represents halogen, C 1-4  alkyl, trifluoromethoxy or trifluoromethyl; R 1  is trifluoromethyl, C 1-4  alkyl, C 1-4  alkoxy, halogen or trifluoromethoxy; R 2  is hydrogen, C 1-4 alkyl or C 2-6 alkenyl; R 3  represents hydrogen or C 1-4 alkyl; n and m are independently 0 or an integer from 1 to 3; and pharmaceutically acceptable salts and solvates thereof, process for their preparation and their use in the treatment of condition mediated by tachykinins and/or by selective inhibition of the serotonin reuptake transporter protein.

[0001] The present invention relates to N-phenyl piperazine derivatives,to processes for their preparation, to pharmaceutical compositionscontaining them and to their medical use.

[0002] U.S. Pat. No. 5,880,128 and WO 9631501 disclose interaliaN′-carbonyl-N aryl piperazine derivatives which inhibit farnesylproteintransferase.

[0003] WO 9846626 and WO 9846627 disclose some N-phenyl-N′ substitutedpiperazine derivatives as factor Xa inhibitors. Such compounds areuseful as inhibitors of blood coagulation in mammalian species.

[0004] WO 9525443 describes certain N-phenyl-N′ substituted piperazinederivatives useful as oxytocin or vasopressin antagonists.

[0005] However in the above cited documents there is neither disclosurenor suggestion of any compound as claimed herein.

[0006] Thus the present invention provides compounds of formula (I)

[0007] wherein

[0008] R represents halogen, C₁₋₄ alkyl, trifluoromethoxy ortrifluoromethyl;

[0009] R₁ is trifluoromethyl, C₁₋₄ alkyl, C₁₋₄ alkoxy, halogen ortrifluoromethoxy;

[0010] R₂ is hydrogen, C₁₋₄ alkyl or C₂₋₆ alkenyl;

[0011] R₃ represents hydrogen or C₁₋₄ alkyl;

[0012] n and m are independently 0 or an integer from 1 to 3;

[0013] and pharmaceutically acceptable salts and solvates thereof.

[0014] A further embodiment of the invention provides compounds offormula (I) and pharmaceutically acceptable salts and solvates thereof,wherein

[0015] R represents halogen or C₁₋₄ alkyl;

[0016] R₁ is trifluoromethyl, C₁₋₄ alkyl, C₁₋₄ alkoxy, halogen ortrifluoromethoxy;

[0017] R₂ is hydrogen, C₁₋₄ alkyl or C₂₋₆ alkenyl;

[0018] R₃ represents hydrogen or C₁₋₄ alkyl;

[0019] n and m are independently 0 or an integer from 1 to 3;

[0020] Suitable pharmaceutically acceptable salts of the compounds ofgeneral formula (I) include acid addition salts formed withpharmaceutically acceptable organic or inorganic acids, for examplehydrochlorides, hydrobromides, sulphates, alkyl- or arylsulphonates(e.g. methanesulphonates or p-toluenesulphonates), phosphates, acetates,citrates, succinates, tartrates, trifluoroacetates, lactates, fumarates,malates and maleates.

[0021] The solvates may, for example, be hydrates.

[0022] References hereinafter to a compound according to the inventioninclude both compounds of formula (I) and their pharmaceuticallyacceptable acid addition salts together with pharmaceutically acceptablesolvates.

[0023] It will be appreciated by those skilled in the art that thecompounds of formula (I) contain at least one chiral centre (namely thecarbon atom shown as * in formula (I)) and these may be represented bythe formulae (1a) and (1b)

[0024] The wedge shaped bond indicates that the bond is above the planeof the paper. The broken bond indicates that the bond is below the planeof the paper.

[0025] The configuration shown for the chiral carbon atom indicated as *in formula 1a is β and in formula 1b is α

[0026] In general, in the specific compounds named below, the βconfiguration at the chiral carbon atom indicated as * corresponds tothe S isomer and the α configuration corresponds to the R isomer.

[0027] Further asymmetric carbon atoms are possible in the compound offormula (I). Thus, for example, when R₂ is C₁₋₄ alkyl or C₂₋₆ alkenyl,the compounds of formula (I) possess at least two asymmetric carbonatoms.

[0028] The assignment of the R and S configuration of the asymmetriccarbon atoms of the compounds of the invention has been made accordingto the rules of Cahn, Ingold and Prelog 1956, 12, 81.

[0029] It is to be understood that all stereoisomeric forms, includingall enantiomers, diastereoisomers and all mixtures thereof, includingracemates, are encompassed within the scope of the present invention andthe reference to compounds of formula (I) includes all stereoisomericforms unless otherwise stated.

[0030] Furthermore, some of the crystalline forms of the compounds ofstructure (I) may exist as polymorphs, which are included in the presentinvention.

[0031] The present invention also includes isotopically-labeledcompounds, which are identical to those recited in formulas I andfollowing, but for the fact that one or more atoms are replaced by anatom having an atomic mass or mass number different from the atomic massor mass number usually found in nature. Examples of isotopes that can beincorporated into compounds of the invention include isotopes ofhydrogen, carbon, nitrogen, oxygen, phosphorous, fluorine, iodine, andchlorine, such as ³H, ¹¹C, ¹⁴C, ¹⁸F, ¹²³I and ¹²⁵I.

[0032] Compounds of the present invention and pharmaceuticallyacceptable salts of said compounds that contain the aforementionedisotopes and/or other isotopes of other atoms are within the scope ofthe present invention. Isotopically-labeled compounds of the presentinvention, for example those into which radioactive isotopes such as ³H,¹⁴C are incorporated, are useful in drug and/or substrate tissuedistribution assays. Tritiated, i.e., ³H, and carbon-14, i.e., ¹⁴C,isotopes are particularly preferred for their ease of preparation anddetectability. ¹¹C and ¹⁸F isotopes are particularly useful in PET(positron emission tomography), and ¹²⁵I are particularly useful inSPECT (single photon emission computerized tomography), all useful inbrain imaging. Further, substitution with heavier isotopes such asdeuterium, i.e., ²H, can afford certain therapeutic advantages resultingfrom greater metabolic stability, for example increased in vivohalf-life or reduced dosage requirements and, hence, may be preferred insome circumstances. Isotopically labeled compounds of formula I andfollowing of this invention can generally be prepared by carrying outthe procedures disclosed in the Schemes and/or in the Examples below, bysubstituting a readily available isotopically labeled reagent for anon-isotopically labeled reagent.

[0033] The term C₁₋₄ alkyl as used herein as a group or a part of thegroup refers to a straight or branched alkyl group containing from 1 to4 carbon atoms; examples of such groups include methyl, ethyl, propyl,isopropyl, n-butyl, isobutyl or tert butyl.

[0034] The term C₂₋₆ alkenyl as used herein refers to a straight orbranched alkenyl group containing from 2 to 6 carbon atoms examples ofsuch groups include vinyl, propenyl, isopropenyl, n-butenyl, isobutenyl,pentenyl, hexenyl and the like.

[0035] The term C₁₋₄ alkoxy as used herein as a group or a part of thegroup refers to a straight or branched alkyl group containing from 1 to4 carbon atoms attached to an oxigen atom; examples of such groupsinclude methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, isobutoxy ortert butoxy.

[0036] The term halogen refers to a fluorine, chlorine, bromine oriodine atom.

[0037] When R represents halogen this is suitably chlorine or morepreferably fluorine or when R is C₁₋₄ alkyl this is suitably methyl.

[0038] When m is 2 or 3, each of the two or three groups R may be thesame or different. Similarly, when n is 2 or 3, each of the two or threeR₁groups may be the same or different.

[0039] Suitable values for R₁ include trifluoromethyl or halogen.

[0040] Suitable values for R₂ and R₃ include hydrogen or methyl.

[0041] For compounds of formula(I) n is preferably 2.

[0042] A preferred class of compound of formula(I) are those wherein Ris selected from trifluromethyl, methyl or halogen,(e.g fluorine), R₁ istrifluoromethyl or halogen, R₃ is methyl, R₂ is methyl or hydrogen and nis 2.

[0043] Preferred compounds according to the invention are:

[0044] (±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid,(3,5-bis-trifluoromethyl-benzyl)-methylamide;

[0045] (±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide;

[0046] (±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid[1-(3,5-dichloro-phenyl)-ethyl]-methylamide;

[0047] (±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-(±methylamide;

[0048] (±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide;

[0049] (±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,4-dibromo-benzyl)-methylamide;

[0050] (±)1-(4-Trifluoromethyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide;

[0051] and enantiomers, diastereoisomers, pharmaceutically acceptablesalts (e.g. hydrochloride) and solvates thereof.

[0052] Particular preferred compounds of the invention are

[0053] (±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide;

[0054] (+)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide;

[0055] (−)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5dichloro-benzyl)-methylamide;

[0056] and amorphous and crystalline forms thereof and pharmaceuticallyacceptable salts (e.g. hydrochloride) and solvates thereof.

[0057] The compounds of the invention are antagonists of tachykininreceptors, including substance P and other neurokinins, both in vitroand in vivo and are thus of use in the treatment of conditions mediatedby tachykinins, including substance P and other neurokinins.

[0058] Tachykinins are a family of peptides that share a commoncarboxyl-terminal sequence (Phe-X-Gly-Leu-Met-NH2). They are activelyinvolved in the physiology of both lower and advanced lifeforms. Inmammalian lifeforms the main tachykinins are subtance P (SP), NeurokininA (NKA) and Neurokinin B (NKB) which act as neurotransmitters andneuromodulators. Mammalian tachykinins may contribute to thepathophysiology of a number of human diseases.

[0059] Three types of tachykinins receptors have been identified, namelyNK1(SP-preferring), NK2 (NKA-preferring) and NK3 (NKB-preferring) whichare widely distributed throughout the central nervous (CNS) andperipheral nervous system.

[0060] Particularly the compounds of the invention are antagonists ofthe NK1 receptor.

[0061] The compounds of the present invention also have activity asselective serotonin reuptake inhibitors (hereinafter referred to asSSRIs) and are thus of use in the treatment of conditions mediated byselective inhibition of the serotonin reuptake transporter protein.

[0062] Thus the compounds of the present invention combine dual activityas tachykinin antagonists, including substance P and other neurokinins,and as SSRIS. In particular, the compounds of the invention combine dualactivity as NK1 receptor antagonists and as SSRIS.

[0063] In those compounds of the invention which exhibitstereoisomererism, this dual NK1 and SSRIs activity may in certain casesbe exhibited by isomeric mixtures, including racemic mixtures or byindividual stereoisomers comprised in a stereoisomeric mixture.

[0064] In some cases the relative level of NK1 and SSRIs activity, invitro or in vivo, may differ between individual stereoisomers of astereisomeric mixture. In some other cases individual stereoisomers mayexibit synergy when present in combination as a stereoisomeric mixturei.e the individual levels of NK1 and SSRIs activity of a stereisomericmixture may be greater than the level of activity associated withindividual stereoisomers comprised in the stereisomeric mixture.

[0065] Thus, in certain compounds of the invention, the enantiomerscomprising a racemic mixture may exhibit synergy such that the levels ofNK1 and SSRIs activity of the racemate are higher than the individuallevels of NK1 and SSRIs activity of the individual enantiomers.

[0066] By virtue of their efficacy as tachykinins receptor (expeciallyNK1 receptor) antagonists and as SSRIs, the compounds of the presentinvention are particularly useful for the treatment of of CNS disordersand psychotic disorders, in particular in the treatment or prevention ofdepressive states and/or in the treatment of anxiety.

[0067] NK₁-receptor binding affinity has been determined in vitro bymeasuring the compounds' ability to displace [3H]-substance P (SP) fromrecombinant human NK₁ receptors expressed in Chinese Hamster Ovary (CHO)cell membranes.

[0068] CHO cell membranes were prepared by using a modification of themethod described by Beattie D. T. et al. (Br. J. Pharmacol,116:3149-3157, 1995). Briefly, ligand binding was performed in 0.2 ml of50 mM HEPES, pH 7.4, containing 3 mM MnCl₂, 0.02% BSA, 0.5 nM[³H]-Substance P (30÷56 Ci/mmol, Amersham), a final membraneconcentration of 20÷30 μg of protein/ml, and the test compounds. Theincubation proceeded at room temperature for 40 min and stopped byfiltration. Non-specific binding was determined using excess ofSubstance P (1 μM) and represents about 6÷10% of the total binding.

[0069] Compounds of the invention were further characterised in afinctional assay for the determination of their effect to inhibit theintracellular calcium increase induced by SP in Human-NK₁-CHO cellsusing FLIPR technology. Briefly, after 30 min incubation with thecytoplasmic calcium indicator Fluo-4 AM (2 μM), cells were washed andincubated in the absence or presence of three different concentrationsof antagonist for 60 min, at 37° C. in Hank's balanced salts with 20 mMHepes, and then non-cumulative concentration-response curves of SP (2pM-300 nM) was performed. The potency of the antagonist (pK_(B) value)was calculated from Schild's analysis.

[0070] The action of the compounds of the invention at the NK₁ receptorand/or serotonin transporter may be determined by using conventionalanimal models. Thus the ability to bind at the NK₁ receptor and/orserotonin tmnsporter was determined using the guinea pig pup isolationcalls model as described by Pettijohn, Psychol. Rep., 1979 and Rupniaket al., Neuropharmacology, 2000.

[0071] Human Serotonin Transporter (hSERT) binding affinity has beendetermined in vitro by the compounds' ability to displace[³H]-Imipramine from human serotonin transporter expressed in HumanEmbryonic Kidney HEK293 cell membranes (Receptor Biology Inc.). For thebinding reaction, 4 nM of [³H]-Imipramine (703 GBq/mmol, Amersham) wereincubated with 0.02 mg/ml of cell membrane and the compound to be testedat different concentrations (7 concentration points) in 50 mM Tris HCl,pH 7.5, 120 mM of NaCl and 5 mM KCl. The reaction was performed for 60min at 4° C. and was terminated by through GF/B Unifilter (pre-soaked in0.5% PEI) using a Cell Harvester (Packard). Scintillation fluid wasadded to each filtered spot and radioactivity was determined using ascintillation counter (TopCount (Packard)). Non-specific binding wasdetermined using Imipramine (100 μM) and represents about 5% of thetotal binding.

[0072] For the preferred compounds of the invention Human SerotoninTransporter binding affinity has been also determined in vitro by thecompounds ability to displace [3H] paroxetine.

[0073] Competition experiments were conducted with duplicatedetermination for each point.

[0074] Msat601 software package was used to elaborate the competitionbinding data.

[0075] IC₅₀ values were converted to K_(i) values using Cheng-Prusoffequation.

[0076] The inhibitory activity of the compounds at the rat serotonintransporter has been determined in vitro using rSERT-LLCPK cells (LLCPKcells tranfected with the rat SERT). The cells have been plated onto96-well plates (60000 cells/well). After 24 hr, cells have been washedin uptake buffer (Hank's balanced salt solution+20 mM Hepes) andpre-incubated for 10 min at RT with 50 μl of buffer containing the testcompounds. 50 μl of 50 nM [3H] Serotonin (5HT) solution (finalconcentration: 25 nM [3H] 5HT) have been added and plates have beenincubated for 7 min at RT, during which cells take up radiolabelled 5HT.Aspirating the solution and rapidly washing the cells with cold bufferhas terminated the uptake.

[0077] The amount of radioactive 5HT incorporated in the cells has beenthen measured by adding the scintillation cocktail directly onto thecells and reading the plate in the Top Count. The data have beendigitally processed to obtain the pIC50 values of the antagonists. ThepKi values have been calculated using the Chen-Prusoff equation.

[0078] Compounds of the invention are useful in the treatment of CNSdisorders and psychotic disorders, in particular in the treatment orprevention of depressive states and/or in the treatment of anxiety asdefined in, but not restricted to, Diagnostic Statistical of mentaldisorder (DSM) IV edition edit by American Psychiatric association andinternational classification Diseases 10th revision (ICD10).

[0079] Thus for example depressive states include Major DepressiveDisorder (MDD),

[0080] including bipolar depression, unipolar depression, single orrecurrent major depressive episodes, recurrent brief depression,

[0081] with or without psychotic features, catatonic features,melancholic features including anorexia, weight loss, atypical features,anxious depression, cyclothymic or postpartum onset.

[0082] Other mood disorders encompassed within the term major depressivedisorders include dysthymic disorder with early or late onset and withor without atypical features, neurotic depression, post traumatic stressdisorders and social phobia; dementia of the Alzheimer's type, withearly or late onset, with depressed mood; vascular dementia withdepressed mood; mood disorders induced by alcohol, amphetamines,cocaine, hallucinogens, inhalants, opioids, phencyclidine, sedatives,hypnotics, anxiolytics and other substances; schizoaffective disorder ofthe depressed type; and adjustment disorder with depressed mood. Majordepressive disorders may also result from a general medical conditionincluding, but not limited to, myocardial infarction, diabetes,miscarriage or abortion, etc.

[0083] The term anxiety includes anxiety disorders, such as panicdisorders with or without agoraphobia, agoraphobia, phobias for examplesocial phobias or agoraphobia, obsessive-compulsive disorder, stressdisorders including post traumatic stress disorder generalised anxietydisorder, acute stress disorders and mixed anxiety-depression disorders.

[0084] Compounds of the invention are useful as analgesics. Inparticular they are useful in the treatment of traumatic pain such aspostoperative pain; traumatic avulsion pain such as brachial plexus;chronic pain such as arthritic pain such as occurring in osteo-,rheumatoid or psoriatic arthritis; neuropathic pain such aspost-herpetic neuralgia, trigeminal neuralgia, segmental or intercostalneuralgia, fibromyalgia, causalgia, peripheral neuropathy, diabeticneuropathy, chemotherapy-induced neuropathy, AIDS related neuropathy,occipital neuralgia, geniculate neuralgia, glossopharyngeal neuralgia,reflex sympathetic dystrophy, phantom limb pain; various forms ofheadache such as migraine, acute or chronic tension headache,temporomandibular pain, maxillary sinus pain, cluster headache;odontalgia; cancer pain; pain of visceral origin; gastrointestinal pain;nerve entrapment pain; sport's injury pain; dysmennorrhoea; menstrualpain; meningitis; arachnoiditis; musculoskeletal pain; low back paine.g. spinal stenosis; prolapsed disc; sciatica; angina; ankylosingspondyolitis; gout; burns; scar pain; itch; and thalamic pain such aspost stroke thalamic pain.

[0085] Compounds of the invention are also useful in the treatment ofsleep disorders including dysomnia, insomnia, sleep apnea, narcolepsy,and circadian ritmic disorders.

[0086] Compounds of the invention are also useful in the treatment orprevention of the cognitive disorders. Cognitive disorders includedementia, amnestic disorders and cognitive disorders not otherwisespecified.

[0087] Furthermore compounds of the invention are also useful as memoryand/or cognition enhancers in healthy humans with no cognitive and/ormemory deficit.

[0088] Compounds of the invention are also useful in the treatment oftolerance to and dependence on a number of substances. For example, theyare useful in the treatment of dependence on nicotine, alcohol,caffeine, phencyclidine (phencyclidine like compounds), or in thetreatment of tolerance to and dependence on opiates (e.g. cannabis,heroin, morphine) or benzodiazepines; in the treatment of cocaine,sedative ipnotic, amphetamine or amphetamine-related drugs (e.g.dextroamphetamine, methylamphetamine) addiction or a combinationthereof.

[0089] Compounds of the invention are also useful as anti-inflammatoryagents. In particular they are useful in the treatment of inflammationin asthma, influenza, chronic bronchitis and rheumatoid arthritis; inthe treatment of inflammatory diseases of the gastrointestinal tractsuch as Croin's disease, ulcerative colitis, inflammatory bowel diseaseand non-steroidal anti-inflammatory drug induced damage; inflammatorydiseases of the skin such as herpes and eczema; inflammatory diseases ofthe bladder such as cystitis and urge incontinence; and eye and dentalinflammation.

[0090] Compounds of the invention are also useful in the treatment ofallergic disorders, in particular allergic disorders of the skin such asurticaria, and allergic disorders of the airways such as rhinitis.

[0091] Compounds of the invention are also useful in the treatment orprevention of schizophrenic disorders including paranoid schizophrenia,disorganised schizophrenia, catatonic schizophrenia, undifferentiatedschizophrenia, residual schizophrenia.

[0092] Compounds of the invention are also useful in the treatment ofemesis, i.e. nausea, retching and vomiting. Emesis includes acuteemesis, delayed emesis and anticipatory emesis. The compounds of theinvention are useful in the treatment of emesis however induced. Forexample, emesis may be induced by drugs such as cancer chemotherapeuticagents such as alkylating agents, e.g, cyclophospharide, carmustine,lomustine and chlorambucil; cytotoxic antibiotics, e.g. dactinomycin,doxorubicin, mitomycin-C and bleomycin; anti-metabolites, e.g.cytarabine, methotrexate and 5-fluorouracil; vinca alkaloids, e.g.etoposide, vinblastine and vincristine; and others such as cisplatin,dacarbazine, procarbazine and hydroxyurea; and combinations thereof;radiation sickness; radiation therapy, e.g. irradiation of the thorax orabdomen, such as in the treatment of cancer, poisons; toxins such astoxins caused by metabolic disorders or by infection, e.g. gastritis, orreleased during bacterial or viral gastrointestinal infection;pregnancy; vestibular disorders, such as motion sickness, vertigo,dizziness and Meniere's disease; post-operative sickness;gastrointestinal obstruction; reduced gastrointestinal motility;visceral pain, e.g. myocardial infarction or peritonitis; migraine;increased intercranial pressure; decreased intercrnnial pressure (e.g.altitude sickness); opioid analgesics, such as morphine; andgastro-oesophageal reflux disease, acid indigestion, over-indulgence offood or drink acid stornach, sour stomach, waterbrash/regurgitation,heartburn, such as episodic heartburn, nocturnal heartburn, andmeal-induced heartburn and dyspepsia.

[0093] Compounds of the invention are also useful in the treatment ofgastrointestinal disorders such as irritable bowel syndrome; skindisorders such as psoriasis, pruritis and sunburn; vasospastic diseasessuch as angina, vascular headache and Reynaud's disease; cerebralischeamia such as cerebral vasospasm following subarachnoid haemorrhage;fibrosing and collagen diseases such as scleroderma and eosinophilicfascioliasis; disorders related to immune enhancement or suppressionsuch as systemic lupus erythematosus and rheumatic diseases such asfibrositis; and cough.

[0094] The compounds of the invention are also useful in premenstrualdysphoric disorder PMDD), in chronic fatigue syndrome and Multiplesclerosis.

[0095] Compounds of the invention have been found to exhibit anxiolyticand antidepressant activity in conventional tests. For example in Guineapig pups separation-induced vocalisations (Molewijk et al., 1996).

[0096] The invention therefore provides a compound of formula (I) or apharmaceutically acceptable salt or solvate thereof for use in therapy,in particular in human medicine.

[0097] There is also provided as a further aspect of the invention theuse of a compound of formula (I) or a pharmaceutically acceptable saltor solvate thereof in the preparation of a medicament for use in thetreatment of conditions mediated by tachykinins (including substance Pand other neurokinins) and/or by selective inhibition of serotoninreuptake.

[0098] There is also provided as a further aspect of the invention theuse of a compound of formula (I) or a pharmaceutically acceptable saltor solvate thereof in the treatment of conditions mediated bytachykinins (including substance P and other neurokinins) and/or byselective inhibition of the serotonin reuptake transporter protein.

[0099] In a further aspect there is provided the use of a compounds offormula(I) or a pharmaceutically acceptable salt or solvate thereof inthe preparation of a medicament for use in the treatment of depressionand /or anxiety.

[0100] In an alternative or further aspect there is provided a methodfor the treatment of a mammal, including man, in particular in thetreatment of conditions mediated by tachykinins, including substance Pand other neurokinins and/or by selective inhibition of the serotoninreuptake transporter protein comprising administration of an effectiveamount of a compound of formula (I) or a pharmaceutically acceptablesalt thereof.

[0101] In a further aspect of the present invention is provided a methodfor the treatment of a manmal, including man, in particular in thetreatment of depression and/or anxiety which method comprisesadministration of an effective amount of a compound of formula (I) or apharmaceutically acceptable salt or solvate thereof.

[0102] It will be appreciated that reference to treatment is intended toinclude prophylaxis as well as the alleviation of established symptoms.

[0103] Compounds of formula (I) may be administered as the raw chemicalbut the active ingredient is preferably presented as a pharmaceuticalformulation.

[0104] Accordingly, the invention also provides a pharmaceuticalcomposition which comprises at least one compound of formula (I) or apharmaceutically acceptable salt or a solvate thereof and formulated foradministration by any convenient route. Such compositions are preferablyin a form adapted for use in medicine, in particular human medicine, andcan conveniently be formulated in a conventional manner using one ormore pharmaceutically acceptable carriers or excipients.

[0105] Thus compounds of formula (I) may be formulated for oral, buccal,parenteral, topical (including ophthalmic and nasal), depot or rectaladministration or in a form suitable for administration by inhalation orinsufflation (either through the mouth or nose).

[0106] For oral administration, the pharmaceutical compositions may takethe form of, for example, tablets or capsules prepared by conventionalmeans with pharmaceutically acceptable excipients such as binding agents(e.g. pregelatinised maize starch, polyvinylpyrrolidone or hydroxypropylmethylcellulose); fillers (e.g. lactose, microcrystalline cellulose orcalcium hydrogen phosphate); lubricants (e.g. magnesium stearate, talcor silica); disintegrants (e.g. potato starch or sodium starchglycollate); or wetting agents (e.g. sodium lauryl sulphate). Thetablets may be coated by methods well known in the art. Liquidpreparations for oral administration may take the form of, for example,solutions, syrups or suspensions, or they may be presented as a dryproduct for constitution with water or other suitable vehicle beforeuse. Such liquid preparations may be prepared by conventional means withpharmaceutically acceptable additives such as suspending agents (e.g.sorbitol syrup, cellulose derivatives or hydrogenated edible fats);emulsifying agents (e.g. lecithin or acacia); non-aqueous vehicles (e.g.almond oil, oily esters, ethyl alcohol or fractionated vegetable oils);and preservatives (e.g. methyl or propyl-p-hydroxybenzoates or sorbicacid). The preparations may also contain buffer salts, flavouring,colouring and sweetening agents as appropriate.

[0107] Preparations for oral administration may be suitably formulatedto give controlled release of the active compound.

[0108] For buccal administration the composition may take the form oftablets or formulated in conventional manner.

[0109] The compounds of the invention may be formulated for parenteraladministration by bolus injection or continuous infusion. Formulationsfor injection may be presented in unit dosage form e.g. in ampoules orin multi-dose containers, with an added preservative. The compositionsmay take such forms as suspensions, solutions or emulsions in oily oraqueous vehicles, and may contain formulatory agents such as suspending,stabilising and/or dispersing agents. Alternatively, the activeingredient may be in powder form for constitution with a suitablevehicle, e.g. sterile pyrogen-free water, before use.

[0110] The compounds of the invention may be formulated for topicaladministration in the form of ointments, creams, gels, lotions,pessaries, aerosols or drops (e.g. eye, ear or nose drops). Ointmentsand creams may, for example, be formulated with an aqueous or oily basewith the addition of suitable thickening and/or gelling agents.Ointments for administration to the eye may be manufactured in a sterilemanner using sterilised components.

[0111] Lotions may be formulated with an aqueous or oily base and willin general also contain one or more emulsifying agents, stabilisingagents, dispersing agents, suspending agents, thickening agents, orcolouring agents. Drops may be formulated with an aqueous or non-aqueousbase also comprising one or more dispersing agents, stabilising agents,solubilising agents or suspending agents. They may also contain apreservative.

[0112] The compounds of the invention may also be formulated in rectalcompositions such as suppositories or retention enemas, e.g. containingconventional suppository bases such as cocoa butter or other glycerides.

[0113] The compounds of the invention may also be formulated as depotpreparations. Such long acting formulations may be administered byimplantation (for example subcutaneously or intramuscularly) or byintramuscular injection. Thus, for example, the compounds of theinvention may be formulated with suitable polymeric or hydrophobicmaterials (for example as an emulsion in an acceptable oil) or ionexchange resins, or as sparingly soluble derivatives, for example, as asparingly soluble salt.

[0114] For intranasal administration, the compounds of the invention maybe formulated as solutions for administration via a suitable metered orunitary dose device or alternatively as a powder mix with a suitablecarrier for administration using a suitable delivery device.

[0115] A proposed dose of the compounds of the invention is 1 to about1000 mg per day. It will be appreciated that it may be necessary to makeroutine variations to the dosage, depending on the age and condition ofthe patient and the precise dosage will be ultimately at the discretionof the attendant physician or veterinarian. The dosage will also dependon the route of administration and the particular compound selected.

[0116] Thus for parenteral administration a daily dose will typically bein the range of 1 to about 100 mg, preferably 1 to 80 mg per day. Fororal administration a daily dose will typically be within the range 1 to300 mg e.g. 1 to 100 mg.

[0117] Compounds of formula (I), and salts and solvates thereof, may beprepared by the general methods outlined hereinafter. In the followingdescription, the groups R, R₁, R₂,R₃, m and n have the meaning aspreviously defined for compounds of formula (I) unless otherwise stated.

[0118] A compound of formula (I) may be prepared by reaction of anactivated derivative of the carboxylic acid of formula (II), whereinR_(a) is a suitable nitrogen protecting group, with amine (III) or saltsthereof, optionally in the presence of a suitable base, followed byremoval of the protecting group R_(a),

[0119] Suitable activated derivatives of the carboxyl group include thecorresponding acyl halide, mixed anhydride, activated ester such as athioester or a derivative formed between the carboxylic acid group and acoupling agent such as that used in peptide chemistry, for exampleO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate.

[0120] The reaction is preferably carried out in an aprotic solvent suchas an ether, e.g. tetrahydrofuran, a halohydrocarbon, e.g.dichloromethane, N,N-dimethylformamide or acetonitrile.

[0121] Suitable base for use in this reaction include organic base suchas triethylamine or N,N diisopropylethylamine.

[0122] The activated derivatives of the carboxylic acid (II) may beprepared by conventional means. A particularly suitable activatedderivative for use in this reaction is obatained by reaction of thecarboxylic acid (II) withO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate in asuitable aprotic solvent such as an ether e.g. tetrahydrofuran, ahalohydrocarbon e.g. dichloromethane, an amide e.g.N,N-dimethylformamide or acetonitrile.

[0123] Compounds of formula (II) may be prepared by treating compoundsof formula (IV) wherein R_(a) has the meaning defined in formula (II),with a compound of formula (V),

[0124] wherein L is a suitable leaving group such as halogen (e.g.chlorine, bromine or iodine) and Rb is an appropriate group capable tobe converted into the carboxylic group, followed by conversion of Rbinto the carboxylic group.

[0125] Suitable Rb groups for use in this reaction include a carboxylprotected group or a cyano group.

[0126] The reaction conveniently takes place in an aprotic solvent suchas a hydrocarbon (e.g. toluene) optionally in the presence of a basesuch as a tertiary amine (e.g. diisopropylethylamine) and preferablywith heating e.g. 40°-120° C.

[0127] When Rb is a carboxyl protected group, example of suitable groupsincludes allyloxycarbonyl, alkyloxycarbonyl (e.g. methoxycarbonyl,ethoxycarbonyl, t-butyloxycarbonyl) arylmethyloxycarbonyl (e.g.benzyloxycarbonyl or p-nitrobenzyloxycarbonyl) and the like.

[0128] When Rb is a carboxyl protected group, the conversion intocarboxylic acid may be carried out using known procedure for removingcarboxylic protecting groups.

[0129] Thus when Rb is methoxycarbonyl or ethoxycarbonyl the conversioninto carboxylic group may be carried out by alkaline hydrolysis using,for example, sodium hydroxide or lithium hydroxide in a suitable solventsuch as tetrahydrofuran or an alkanol e.g. methanol or isopropanol.

[0130] When Rb is a cyano group, the conversion into the carboxylicgroup may be carried out by reduction of the cyano group with lithiumaluminum hydride.

[0131] Compounds of formula (IV) may be prepared by reduction of anamide compound of formula (VI)

[0132] An appropriate reducing agent for this reaction includes forexample borane or a borohydride, e.g. sodium borohydride, sodiumborohydride, sodium cyanoborohydride or triacetoxy borohydride.

[0133] The reaction conveniently takes place in a suitable solvent suchas alcohol (i.e. ethanol or methanol) at a temperature ranging betweenroom temperature and reflux temperature.

[0134] A compound of formula (VI) may be prepared by alkylation of acompound of formula (VII), wherein R_(a) represents a nitrogenprotecting group and L is a leaving group as defined above, with amine(VIII).

[0135] The reaction may be carried out in an aprotic solvent such asdichloromethane or alkyl esters (e.g. ethylacetate) and in the presenceof an organic base such as triethylamine.

[0136] When R_(a) is a nitrogen protecting group, examples of suitablegroups include alkoxycarbonyl e.g. t-butoxycarbonyl, benzyloxycarbonyl,arylsulphonyl e.g. phenylsulphonyl, arylmethyl e.g benzyl or2-triiethylsilylethoxymethyl.

[0137] Protection and deprotection may be effected using conventionaltechniques such as those described in “Protective Groups in OrganicSynthesis 2^(nd) Ed.” by T. W. Greene and P. G. M. Wuts (John Wiley andSons, 1991) and as described in the examples hereinafter.

[0138] Thus when R_(a) is a benzyl group, this may be removed byhydrogenation in a suitable solvent such as ethanol or methanol or byhydrolysis in the presence of haloformiates such as for examplechloroformiates and in the presence of a suitable organic base.

[0139] In a preferred embodiment of the invention compound of formula(IV) may be prepared by reaction of a compound of formula(IX), wherein Lis a suitable leaving group such as halogen (i.e chlorine or bromine) ormesilate, with NH₂Ra wherein Ra is a suitable nitrogen protecting group.

[0140] The reaction conveniently takes place in an aprotic solvent suchas an aprotic solvent optionally in the presence of a base such as atertiary amine and preferably with heating e.g. 40°-120° C.

[0141] Compounds of formula (VII) and (VIII) are commercially available.

[0142] Compounds of formula (IX) may be prepared by analogous methods tothose used for known compounds.

[0143] Thus for example compounds of formula (IX) may be preparedaccording to the preparation described in Tulyaganov, S. R. andKhasanov, S. A, Uzb. Khim. Zh. (1971), 15(2), 62-4) or Sineokov, A. etal., Zh. Org. Khim. (1968), 4(2), 284-7.

[0144] The compounds of formula (I) may be readily isolated inassociation with solvent molecules by crystallisation from orevaporation of an appropriate solvent to give the correspondingsolvates.

[0145] When a specific enantiomer of a compound of general formula (I)is required, this may be obtained for example by resolution of acorresponding enantiomeric mixture of a compound of formula (I) usingconventional methods.

[0146] Thus, specific enantiomers of the compounds of formula (I) may beprepared by reaction of a suitable chiral alcohol, in the presence of asource of a carbonyl group (such as triphosgene or carbonyl diimidazole)separating the resulting diastereoisomeric carbamates by conventionalmeans, e.g. chromatography or by fractional crystallisation. Therequired enantiomer of a compound of general formula (I) may be isolatedby removal of carbamate and conversion into the required free base orsalts thereof.

[0147] Suitable chiral alcohols for use in the process include(R)-sec-phenylethyl alcohol.

[0148] Alternatively, the required enantiomer may be obtained fromracemic compounds of formula (I) by use of chiaral HPLC procedures.

[0149] Alternatively, enantiomers of a compound of general formula (I)may be synthesised from the appropriate optically active intermediatesusing any of the general processes described herein. Thus, for example,the required enantiomer may be prepared by the correspondingenantiomeric acid of formula (II) using any of the process describedabove for preparing compounds of formula (I) from the acid (II).

[0150] The single enantiomer of acid (III) may be prepared from theracemic acid (III) using conventional procedures such as salt formationwith a suitable optically active amine, such as (R)-α-phenylethylamine,(S)-α-phenylethylamine, brucine, cinconidine, quinine, followed byseparation of the two diasteroisomer salts obtained and regeneration ofthe free acid. The two diasteroisomer salts may be convenientlyseparated by conventional means such as fractionally crystallisation orby chromatography.

[0151] In a further embodiment of the invention the specific enantiomerof acid (II) may by prepared by esterification of racemic acid (II) witha suitable optically active alchool, separating the resultingdiastereoisomeric esters by conventional means e.g. chromatography,followed by hydrolysis of the required single diastereomeric ester.

[0152] Suitable chirals alcohols for use in this process includeS(+)-indanol, S(+)methylmandelate, S(−) methyl lactate or R(+) t-butyllactate.

[0153] The diastereoisomeric esters of a compound of formula (II) may beprepared by conventional means such as reaction of the chiral alcoholwith an activated derivative of a compound of formula (II) in an aproticsolvent such as ether e.g. tetrahydrofuran.

[0154] The activated derivative of a compound of formula (II) may beprepared from a compound of formula (II) using conventional means forpreparing activated derivatives of a carboxylic acid groups such asthose conveniently used in peptide synthesis.

[0155] A convenient method of preparing the diastereoisomeric esters ofa compound of formula (II) is to prepare the activated derivative of acompound of formula (II) in the presence of the chiral alcohol.

[0156] Thus, for example, a compound of formula (II) may be treated withthe Mitsunobu combination of reagents, i.e. a dialkylazo-dicarboxylatesuch as diethylazodicarboxylate and a triarylphosphine e.g.triphenylphosphine in the presence of the chiral alcohol.

[0157] The reaction conveniently takes place in the presence of asuitable solvent such as an ether (e.g. diethylether ortetrahydrofiran), a halohydrocarbon (e.g. diethylether ortetrahydrofuran), a halohydrocarbon (e.g. dichloromethane) or a nitrile(e.g. acetonitrile) or a mixture thereof, at a temperature ranging from0-30° C.

[0158] The required single diastereoisomeric ester of a compound offormula (I) substantially free of the other diastereoisomers may beobtained from the mixture thereof by conventional means, for example bythe use of conventional chromatographic procedures such as preparativeHPLC or by fractional crystallization.

[0159] The required enantiomer may be prepared from the correspondingsingle diastereoisomeric ester of a compound of formula (I) byhydrolysis, e.g. alkaline hydrolysis. Thus, for example, the hydrolysismay be carried using an alkali metal hydroxide e.g. sodium hydroxide orlithium hydroxide in a solvent such as an ether, e.g. tetrahydrofuran,and water.

[0160] Physiologically acceptable salts of compounds of formula (I) maybe prepared by treating the corresponding base with an appropriate acidin a suitable solvent.

[0161] The invention is further illustrated by the followingIntermediates and Examples which are not intended as a limitation of theinvention.

[0162] Pharmaceutically acceptable salts may also be prepared from othersalts, including other pharmaceutically acceptable salts, of thecompound of formula (I) using conventional methods

[0163] In the Intermediates and Examples unless otherwise stated:

[0164] Melting points (m.p.) were determined on a Gallenkamp m.p.apparatus or a Büchi 530 melting point apparatus and are uncorrected.All temperatures refers to ° C. Infrared spectra were measured on aFT-IR instrument. ¹H-NMR spectra were recorded at 400 or 500 MHz,chemical shifts are reported in ppm (δ) using the residual solvent lineas internal standard. The signals are assigned as singlets (s), doublets(d), doublets of doublets (dd), triplets (t), quartets (q) or multiplets(m). Flash column chromatography was carried out over silica gel (MerckAG Darmstaadt, Germany). SFC (Supercritical Fluid Chromatography wasperformed on a Diacel chiral pack AD column (25×0.46 cm i.d., 5 μm)using the following conditions: column oven temperature 35° C., mobilephase carbon dioxide +35% EtOH (with 0.1% vv isopropylamine), flow 2.5mL/min, UV detection at 225 nm.

[0165] The following abbreviations are used in the text: AcOEt=ethylacetate, CH=cyclohexane, DCM=dichloromethane, EtOH=ethanol, Et2O=diethylether, DIPEA=N,N-diisopropylethylamine, DMF=N,N′-dimethylformamide,MeOH=methanol, TEA=triethylamine, TFA=trifluoroacetic acid,THF=tetrahydrofuran. Tlc refers to thin layer chromatography on silicaplates, and dried refers to solution dried over anhydrous sodiumsulphate; r.t. (RT) refers to room temperature.

[0166] Enantiomer 1, enantiomer 2, diastereoisomer 1 or diastereoisoiner2 refer to a single enantiomer or a single diasteroisomer respectively,whose absolute stereochemistry was not characterised.

[0167] Diastereoisomer A or diastereoisomer B refer to a mixture of twodiastereoisomers whose absolute stereochemistry was not characterised.

[0168] The X-ray powder diffraction pattern of a crystalline form of thecompounds of the invention was obtained by loading the sample into thediffractometer (Siemens D5005 X-ray diffractometer equipped with θ/θgoniometer, scintillation counter and graphite monochromator. Thediffractometer was set up with the instrumental parameters given below:

[0169] Instrumental Parameters

[0170] MONOCHROMANIC RADIATION: Cu-1.54056/1.54439

[0171] 2θRANGE: 2°-45° 2θ

[0172] GENERATOR VOLTAGE/CURRENT: 40 kV/50 mA

[0173] STEP SIZE: 0.02° 2θ

[0174] TIME PER STEP: 10 sec

[0175] ROTATION: on

[0176] DIVERGENCE/ANTISCATTERING SLIT: variable

[0177] SAMPLE HOLDER: on zero-background plate.

[0178] The spectrum obtained was analysed using the data evaluationsoftware EVA3.0.

[0179] Intermediate 1

N-Benzyl-2-(4-fluoro-2-methyl-phenylamino)acetamide

[0180] A solution of chloroacetyl chloride (11.4 mL) was added drop-wiseover 1 hour to a stirred solution of benzylamine (15 mL) and TEA (23 mL)in dry TFP (200 mL) previously cooled at 0-3° C. under a Nitrogenatmosphere. The dark suspension was allowed to warm gradually to r.t.and then stirred at r.t. for 3 hours. The inorganic salts were filteredand washed with AcOEt (300 mL). The filtrate was washed with 2Nhydrochloric acid solution (2×250 mL), sodium hydrogen carbonate (2×200mL) and water (200 mL). The organic layer was dried and concentrated invacuo to give a dark solid, which was crystallized from Et₂O/CH (1:1,700 mL) to give N-benzyl-2-chloroacetamide (17.8 g) as a grey solid(T.l.c.: AcOEt 100%, Rf=0.47).

[0181] A mixture of N-benzyl-2-chloroacetamide (17.8 g), DIPEA (19.5 mL)and 4-fluoro-2-methyl-aniline (10.6 mL) in anhydrous DMF (174 mL) wasstirred at 100° C. for 40 hours under a Nitrogen atmosphere. Aftercooling to r.t., the dark solution was partitioned between AcOEt (200mL) and water (200 mL). The separated aqueous phase was extracted withfurther AcOEt (3×200 mL). The combined organic extracts were washed withwater (200 mL), dried and concentrated in vacuo. The residue waspurified by flash chromatography (CH/AcOEt 2:8) to give a dark solid,which was triturated with CH to give the title compound as a beige solid(16.2 g).

[0182] T.l.c.: AcOEt/CH 8:2, Rf=0.48.

[0183] M.p.: 75-76° C.

[0184] IR (nujol, cm⁻¹): 3395 and 3294 (NH), 1642 (C═O).

[0185]¹H-NMR (d₆-DMSO): δ (ppm) 8.39 (t, 1H); 7.26 (t, 2H); 7.19 (t,1H); 7.18 (d, 2H); 6.87 (dd, 1H); 6.81 (td, 1H); 6.28 (dd, 1H); 5.25 (t,1H); 4.27 (d, 2H); 3.7 (d, 2H); 2.12 (s, 3H).

[0186] MS (AB/NBA): m/z=272 [M]⁺.

[0187] Intermediate 2

N-Benzyl-N′-(4-fluoro-2-methyl-phenyl)-1,2-ethylenediamine

[0188] Method A

[0189] Borane (1M solution in THF, 30.4 mL) was added drop-wise at r.t.to a solution of intermediate 1 (1 g) in dry TBF (100 mL) under aNitrogen atmosphere. The mixture was heated to reflux for 24 hours, thenit was cooled to r.t., poured into conc. hydrochloric acid and extractedwith AcOEt. The organic phase was concentrated in vacuo, was diluted inDCM and washed with a solution of potassium hydroxide until the aqueousphase has pH=7. The organic phase was dried and concentrated in vacuo togive the title compound (0.86 g) as a whitish wax.

[0190] T.l.c.: AcOEt 100%, Rf=0.14.

[0191]¹H-NMR (d₆-DMSO): δ (ppm) 7.33 (m, 5H); 6.82 (m, 2H); 6.48 (dd,1H; 4.68 (bt, 1H); 3.76 (s, 2H); 3.13 (bm, 211); 2.76 (t, 2H); 2.07 (s,3H).

[0192] MS (ES/+): m/z=259 [M]⁺.

[0193] Method B

[0194] TEA (1.86 mL) was added over 15 minutes to a solution ofintermediate 60 (1 g) is suspended in AcOEt (8 mL) at 20° C. Theresulting mixture was cooled to 5° C. and methanesulfonyl chloride (0.61g) was added in 30 minutes keeping the internal temperature under 10° C.Once finished the addition the mixture was heated to 15° C. The organicmixture was washed with a saturated ammonium chloride solution (3×4 mL)and with water (4 mL). The solution was concentrated to 4 mL and AcOEt(4 mL) was added. Finally it was concentrated again to 4 mL andbenzylamine (2.08 g) was added. The mixture was heated to 50° C. for 1hour then AcOEt (4 mL) was added and the resulting solution was heatedat 78° C. for 15-20 hours.

[0195] The following day the mixture was cooled to 20° C. and washedwith a 13% ammonium chloride solution (5×5 mL) and H2O (5 mL). Theorganic was concentrated to 4 mL and AcOEt (5 mL) is added. Undersuitring at 20° C. hydrochloric acid (5-6N in isopropanol—1.25 mL) wasdropped. The precipitate was then stirred for 2 hours. The solid wasfiltered and washed with AcOEt (3 mL)and then dried for 18 hours at 40°C. to obtain the title compound.(1.19 g)

[0196]¹H-NMR (d₆-DMSO): δ (ppm) 9.74 (bs, 2H); 7.62 (m, 2H); 7.41 (m,3H);6.92 (dd, 1H); 6.88 (dt, 1H); 6.72 (bm, 1H); 4.17 (bs, 2H); 3.50 (t,2H); 3.13 (bm, 2H); 2.18 (s, 3H).

[0197] Intermediate 3

4-Benzyl-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid ethylester

[0198] A solution of intermediate 2 (3.3 g) and DIPEA (7.3 mL) intoluene (40 mL) was added to a solution of ethyl 2,3-dibromopropionate(3.7 mL) in toluene (70 mL) previously heated at 50° C. under a Nitrogenatmosphere. The mixture was then stirred at 100°-105° C. for 19 hours.The mixture was cooled to r.t., then diluted with AcOEt (150 mL) andtoluene (50 mL) and washed with water (150 mL). The separated organicphase was concentrated in vacuo and the residue was purified by flashchromatography (CH/AcOEt 9:1) to give the title compound (1.3 g) as ayellow oil.

[0199] T.l.c.: CH/AcOEt 9:1, Rf=0.44.

[0200] IR (film, cm⁻¹): 1741 (C═O), 1497 (C═C).

[0201]¹ H-NMR (d₆-DMSO): δ (ppm) 7.2-7.35 (m, 5H); 7.16 (dd, 1H); 6.95(dd, 1H); 6.9 (td, 1H); 3.84 (m, 1H); 3.8-3.4 (m, 2H); 3.6 (d, 1H); 3.47(bm, 1H); 3.41 (d, 1H); 2.79 (m, 1H); 2.71 (m, 1H); 2.64 (m, 1H); 2.57(bd, 1H); 2.43 (bt, 1H); 2.21 (s, 3H); 0.97 (t, 3H).

[0202] MS (ES/+): m/z=357 [M+H]⁺.

[0203] Intermediate 4

4-Benzyl-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid

[0204] A solution of intermediate 3 (1.3 g) in MeOH (42 mL) containing1M aqueous lithium hydroxide solution (7.2 mL) was stirred at 70° C. for20 hours. The solution was allowed to cool to r.t., neutralized with 1Nhydrochloric acid and concentrated in vacuo. The residue was dilutedwith AcOEt (30 mL) and washed with water (25 mL). The aqueous phase wasfurther extracted with AcOEt (2×10 mL). The combined organic extractswere dried and concentrated in vacuo to give the title compound (1.2 g)as a white foam.

[0205] T.l.c.: CH/AcOEt 8:2, Rf=0.16.

[0206] IR (film, cm⁻¹): 3397 (NH), 1733 (C═O).

[0207]¹H-NMR (d₆-DMSO): δ (ppm) 12.4 (bs, 1H); 7.37 (m, 5H); 7.12 (dd,1H); 6.97 (dd, 2H); 4.0-3.7 (mn, 2H); 3.5-2.5 (m, 6H); 2.25 (s, 3H).

[0208] MS (ES/+): m/z=329 [M+H]⁺.

[0209] Intermediate 4a

4-Benzyl-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acidhydrochloride

[0210] Intermediate 3 (1 g) was suspended in MeOH (6 mL), isopropanol (2mL) and a 1M sodium hydroxide solution (8 mL). The reaction mixture washeated to 75-78° C. over 4-5 hours. Then the mixture was cooled to 50°C. and concentrated to 9 mL. The mixture was cooled to 25° C. then AcOEt(15 mL) was added and a 10% hydrochoric acid solution (3 mL) was droppedover 10 minutes.

[0211] The two phases were separated and the aqueous one was extractedwith further AcOEt (10 mL). The combined organic extracts wereconcentrated to 4 mL then AcOEt (8 mL) was added and concentrated to 4mL. Finally AcOEt (8 mL) was added and concentrated again to 4 mL.

[0212] AcOEt (3.5 mL) was added and if no precipitated was observed aseed was added. Then methyl-tert-butyl-ether (2.5 mL) was dropped toincrease precipitation and the obtained solid was stirred overnight atroom temperature. It was then filtered and washed withAcOEt/methyl-tert-butyl-ether 1/1 (2 mL).

[0213] After drying at 40° C. in a vacuum oven (12 hours) the titlecompound (0.8 g) was obtained as a white solid.

[0214]¹H-NMR (d₆-DMSO): δ (ppm) 13.0-11.9(2bs, 2H); 7.66 (bs, 2H); 7.47(m, 3H);7.12 (m, 1H); 6.99 (m, 2H); 4.46-4.36 (bd, 2H); 4.3 (b, 1H);3.8-2.9 (bm, 6H); 2.27 (bs, 3H).

[0215] Intermediate 5

4-Benzyl-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide

[0216] DIPEA (1.6 mL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (1.2g) were added to a solution of intermediate 4 (1 g) in anhydrous DMF (50mL) under a Nitrogen atmosphere. After stirring for 5 minutes,3,5-bis(trifluoromethyl)-benzyl-methylamine hydrochloride (0.94 g) wasadded and the mixture was stirred at r.t. for 16 hours. The orangesolution was partitioned between AcOEt (150 mL) and water (150 mL). Theseparated aqueous phase was further extracted with AcOEt (2×100 mL). Thecombined organic extracts were washed with water (3×100 mL), dried andconcentrated in vacuo to a residue which was purified by flashchromatography (CH/AcOEt 1:1) to give the title compound (1.4 g) asyellow oil.

[0217] T.l.c.: AcOEt/CH 6:4, Rf=0.57.

[0218] IR (film, cm⁻¹): 1652 (C═O).

[0219]¹H-NMR (d₆-DMSO): δ (ppm) 7.88 (s, 1H); 7.55 (s, 2H); 7.4-7.2 (m,4H); 7.0 (m, 1H); 7.14 (d, 1H); 6.8-6.75 (m 2H); 4.6 (m, 1H); 4.4 (m,2H); 3.59 (s, 2H); 3.02 (s, 3H); 3.0-2.3 (m, 6H); 2.2 (s, 3H).

[0220] MS (ES/+): m/z=568 [M+H]⁺.

[0221] Intermediate 6

1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid ethyl ester

[0222] A mixture of the intermediate 3 (1.0 g) in EtOH (100 mL)containing glacial acetic acid (1 mL) and 10% palladium on carbon (400mg) was stirred under hydrogen at 5 atm. for 19 hours. The mixture wasfiltered through a pad of celite, and the filtrate was concentrated invacuo. The residue was dissolved in AcOEt and the solution was washedwith a saturated sodium carbonate solution. The organic layer was driedand concentrated in vacuo to give the title compound (910 mg) as ayellow oil.

[0223] T.l.c.: AcOEt/MeOH 8:2, Rf=25.

[0224] IR (CDCl₃, cm⁻¹): 1730 (C═O).

[0225]¹H-NMR (CDCl₃): δ (ppm) 7.11 (m, 1H); 6.9-6.8 (m, 2H); 4.02 (m,2H); 3.71 (t, 1H); 3.43 (m, 1H); 3.24 (m, 2H); 3.1-2.98 (m, 2H); 2.66(m, 1H); 2.31 (s, 3H); 1.1 (t, 3H).

[0226] MS (ES/+): m/z=267 [M+H]⁺.

[0227] Intermediate 7

4-(4-Fluoro-2-methyl-phenyl)-piperazine-1,3-dicarboxylic acid1-tert-butyl ester 3-ethyl ester

[0228] Di-tert-butyl-dicarbonate (821 mg) and TEA (1.2 mL) were added toa solution of intermediate 6 (910 mg) in anhydrous DCM (50 mL) under aNitrogen atmosphere. The solution was stirred at r.t. for 4 hours, thenconcentrated in vacuo. The residue was purified by flash chromatography(CH/AcOEt 8:2) to give the title compound (1.2 g) as a yellow oil.

[0229] T.l.c.: CH/AcOEt 1:1, Rf=0.64.

[0230] IR (CDCl₃, cm⁻¹): 1732 and 1689 (C═O).

[0231]¹H-NMR (CDCl₃): δ (ppm) 7.14 (dd, 1H); 6.9-6.8 (m, 2H); 4.05 (m,2H); 3.95 (m, 1H); 3.73 (m, 3H); 3.45 (m, 2H); 2.7 (m, 1H); 2.31 (s,3H); 1.48 (s, 9H); 1.12 (t, 3H).

[0232] MS (ES/+): m/z=367 [M+H]⁺, 389 [M+Na]⁺.

[0233] Intermediate 8

4(4-Fluoro-2-methyl-phenyl)-piperazine-1,3-dicarboxylic acid1-tert-butyl ester)

[0234] A solution of lithium hydroxide hydrate (0.63 g) in water (5 mL)was added to a solution of intermediate 7 (1.2 g) in MeOH (40 mL). Themixture was heated to 70° C. for 4 hours. The solution was allowed tocool to r.t, neutralised with 1N hydrochloric acid solution until pH=5and extracted with DCM. The organic layer was dried, concentrated invacuo and the residue was purified by flash chromatography (CH/AcOEtfrom 7:3 to 3:7) to give the title compound (770 mg) as pale yellowsolid.

[0235] T.l.c.: CH/AcOEt 1:1, Rf=0.23.

[0236]¹H-NMR (d₆-DMSO): δ (ppm) 13.0-12.0 (bm, 1H); 7.13 (m, 1H); 6.92(m, 1H); 6.86 (m, 1H); 3.7 (m, 1H); 3.7-3.65 (m, 2H); 3.55 (m, 1H);3.39-3.25 (m, 2H); 2.55 (m 1H); 2.26 (s, 3H); 1.41 (s, 9H).

[0237] MS (ES/+): m/z=339 [M+H]⁺.

[0238] Intermediates 8a and 8b

3-[1-(3,5-Dichloro-phenyl)ethyl]-methylcarbamoyl]-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester (8a-diastereoisomer A)3-[1-(3,5-Dichloro-phenyl)-ethyl]-methylcarbamoyl]-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester (8b-diastereoisomer B)

[0239] DIPEA (127 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate(98.7 mg) were added to a solution of intermediate 8 (80 mg) inanhydrous DMF (4 mL) under a Nitrogen atmosphere. After stirring for 5minutes, intermediate 62 (35 mg) was added and the mixture was stirredat r.t. for 18 hours. The solution was diluted with water (10 mL) andextracted with AcOEt (2×20 mL). The combined organic extracts werewashed with brine (10 mL), dried and concentrated in vacuo. The residuewas purified twice by flash chromatography (CH/AcOEt 9:1 the first time,then toluene/AcOEt 95:5) to give the title compound as:

[0240] diastereoisomer A (33 mg—T.l.c.: CH/AcOEt 6:4, Rf=0.6)

[0241] diastereoisomer B (28 mg—T.l.c.: CH/AcOEt 6:4, Rf=0.56).

[0242] Intermediate 9

3-[(3,5-Dichloro-benzyl)-methylcarbamoyl]-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0243] DIPEA (8 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (60mg) were added to a solution of intermediate 8 (50 mg) in anhydrous DMF(5 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,3,5-dichloro-benzyl-methylamine hydrochloride (35 mg) was added and themixture was stirred at r.t. for 16 hours. The solution was partitionedbetween AcOEt (15 mL) and water (15 mL). The separated aqueous phase wasfurther extracted with AcOEt (2×10 mL). The combined organic extractswere washed with water (3×100 mL), dried and concentrated in vacuo to aresidue which was purified by flash chromatography (CH/AcOEt from 9:1 to8:2) to give the title compound (65 g) as yellow oil.

[0244] T.l.c.: AcOEt/CH 6:4, Rf=0.61.

[0245] MS (ES/+): m/z=510 [M+H]⁺.

[0246]¹H-NMR (d₆-DMSO—90° C.): δ (ppm) 7.37 (bs, 1H); 7.16 (m, 1H); 6.93(m, 1H); 6.92 (bs, 2H); 6.83 (m, 1H); 4.59 (d, 1H); 4.1 (bd, 1H);4.3-3.2 (bm, 6H); 2.96 (bs, 3H); 2.57 (m, 1H); 2.29 (bs, 3H); 1.43 (s,9H).

[0247] Intermediate 9a

4-Benzyl-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide

[0248] To a suspension of intermediate 4a (1 g) in DMF (3 mL) a solutionof DIPEA (2.15 mL) was added. The mixture was stirred at roomtemperature over 10 minutes before the addition ofO-benzotriazol-1-yl-N,N,N′,N′-tetramethyluronium tetrafluoroborate(TBTU) (1.05 g). The reaction was stirred over 10 minutes then 3.5dichloro-benzyl methylamine hydrochloride (0.64 g) was added. The soobtained solution was maintained at room temperature for 2 hours. Thesolution was diluted with AcOEt (6 mL) and water (6 mL). The two phaseswere separeted and the organic layer was washed with additional water(3×6 mL).

[0249] The organic phase was diluted with AcOEt (6 mL) and concentratedto 6 mL. This operation was repeated again to remove the water to obtainthe title compound (1.3 g)

[0250]¹H-NMR (d₄-DMSO): δ (ppm) 7.29 (m, 5H); 7.06 (dd, 1H); 7.00 (m,1H);6.93 (m, 1H); 4.5-4.45 (2d, 2H); 3.8 (d, 1H); 3.7 (m, 1H); 3.42 (bd,1H); 3.25 (b, 1H); 3.04 (bs,3H); 2.96 (m, 2H); 2.78 (m, 2H); 2.41 (b,1H); 2.20 (s, 3H).

[0251] Intermediate 10

4-Benzyl-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid1-(S)-tert-butoxycarbonyl-ethyl ester

[0252] A solution of diethylazodicarboxylate (1.19 g) in anhydrous TBF(20 mL) was slowly dropped into a solution of intermediate 4 (1.13 g),triphenylphosphine (1.8 g) and R-(+)-tert-butyl lactate (0.95 g) inanhydrous THF (40 mL) under a Nitrogen atmosphere. The solution wasstirred at r.t. for 24 hours, then further triphenylphosphine (0.9 g)was added followed by a solution of diethyl azodicarboxylate (0.5 mL) inanhydrous THF (5 mL). The solution was stirred for further 2 hours, thenit was concentrated in vacuo. The residue was purified by flashchromatography (CH/Et2O 9:1) to give:

[0253] 343 mg diastereoisomer 1 (intermediate 10a)

[0254] 324 mg of diastereoisomer 2 (intermediate 10b)

[0255] Intermediate 10a

4-Benzyl-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid,1-(S)-tert-butoxycarbonyl-ethyl ester (diastereoisomer 1)

[0256] T.l.c.: CH/Et2O 8:2, Rf=0.38.

[0257] IR (film, cm⁻¹): 1745 (C═O).

[0258]¹H-NMR (d₆-DMSO): δ (ppm) 7.31 (d, 2H); 7.27 (t, 2H); 7.2 (t, 1H);7.13 (dd, 1H); 6.91 (dd, 1H); 6.86 (td, 1H); 4.62 (q, 1H); 3.92 (bt,1H); 3.53 (d, 1H); 3.48 (d, 1H) 3.24 (m, 1H); 2.72 (bm, 2H); 2.64 (m,1H); 2.5 (m, 2H); 2.19 (s, 3H); 1.27 (s, 9H); 1.21 (d, 3H).

[0259] MS (ES/+): m/z=457 [M+H]⁺.

[0260] Intermediate 10b

4Benzyl-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid,1-(S)-tert-butoxycarbonyl-ethyl ester (diastereoisomer 2)

[0261] T.l.c.: CH/Et2O 8:2, Rf=0.37.

[0262] IR (nujol, cm⁻¹): 1746 (C═O).

[0263]¹H-NMR (d₆-DMSO): δ (ppm) 7.3-7.25 (m, 4H); 7.23-7.19 (m, 1H);7.15 (dd, 1H); 6.9 (dd, 1H); 6.83 (td, 1H); 4.66 (q, 1H); 3.85 (m, 1H);3.59 (d, 1H); 3.49 (m, 1H); 3.42 (d, 1H); 2.85 (dd, 1H); 2.72 (m, 1H);2.65 (m, 1H); 2.59 (dd, 1H); 2.43 (m, 1H); 2.2 (s, 3H); 1.23 (s, 9H);1.1 (s, 3H).

[0264] MS (ES/+): m/z=457 [M+H]⁺.

[0265] Intermediate 11

4-(4-Fluoro-2-methyl-phenyl)-piperazine-1,3-dicarboxylic acid3-(S)-tert-butoxycarbonyl-ethyl ester 1-tert-butyl ester(diastereoisomer 1)

[0266] A mixture of intermediate 10a (343 mg), palladium over charcoal(10%-110 mg) and acetic acid (150 μL) in EtOH (15 mL) was hydrogenatedat 6 atm for 16 hours. The catalyst was filtered off and the filtratewas concentrated in vacuo to give1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid1-(S)-tert-butoxycarbonyl-ethyl ester (324 mg). Di tert-butyldicarbonate (211 mg) was added to a solution of1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid1-(S)-tert-butoxycarbonyl-ethyl ester (324 mg) and TEA (933 μL) inanhydrous DCM (10 mL), previously cooled to 0° C. under a Nitrogenatmosphere. The solution was allowed to warm to r.t. and stirred at r.t.for 2 hours. The solution was concentrated in vacuo and the residue waspurified by flash chromatography (CH/AcOEt 8:2) to give the titlecompound (250 mg) as a yellow oil.

[0267] T.l.c.: CH/AcOEt 8:2, Rf=0.64.

[0268]¹ H-NMR (d₆-DMSO): δ (ppm) 7.15 (dd, 1H); 6.96 (dd, 1H); 6.89 (td,1H); 4.72 (q, 1H); 3.87 (m, 1H); 3.74 (m, 1H); 3.7 (m, 1H); 3.55 (m,1H); 3.43 (m, 1H); 3.24 (m, 1H); 2.7 (m, 1H); 2.28 (s, 3H); 1.42 (s,9H); 1.36 (s, 9H); 1.25 (d, 3H).

[0269] MS (ES/+): m/z=467 [M+H]⁺.

[0270] Intermediate 12

4(Fluoro-2-methyl-phenyl)-piperazine-1,3-dicarboxylic acid 1-tert-butylester (enantiomer 1)

[0271] A solution of lithium hydroxide monohydrate (90 mg) in water (5mL) was added to a solution of intermediate 11 (250 mg) in MeOH (5 mL)and the resulting solution was heated to 80° C. for 2 hours. The mixturewas concentrated in vacuo to half volume, treated with 5% hydrochloricacid solution until pH=5 and extracted with AcOEt. The organic phase wasdried and concentrated in vacuo to give the title compound (150 mg) as awhite foam.

[0272] T.l.c.: CH/AcOEt 1:1, Rf=0.45.

[0273]¹H-NMR (d₆-DMSO): δ (ppm) 12.6 (bs, 1H); 7.14 (dd, 1H); 6.96 (dd,1H); 6.9 (dt, 1H); 3.82-3.72 (bs, 1H); 3.7-3.55 (m, 2H); 3.42-3.34 (m,3H); 2.62 (m, 1H); 2.27 (s, 3H); 1.42 (s, 9H).

[0274] MS (ES/+): m/z=339 [M+H]⁺.

[0275] Intermediate 13

3-[(3,5-Dichloro-benzyl)-methylcarbamoyl]-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester (enantiomer 1)

[0276] DIPEA (236 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (182mg) were added to a solution of intermediate 12 (150 mg) in anhydrousDMF (10 mL) under a Nitrogen atmosphere. After stirring for 10 minutes,3,5-chloro-benzyl-methylamine hydrochloride (110 mg) was added and themixture was stirred at r.t. for 4 hours. The solution was partitionedbetween AcOEt (15 mL) and water (15 mL). The organic extracts werewashed with water and brine, dried and concentrated in vacuo to aresidue, which was purified by flash chromatography (CH/AcOEt 8:2) togive the title compound (167 mg) as a yellow oil.

[0277] T.l.c.: AcOEt/CH 1:1, Rf=0.6.

[0278] MS (ES/+): m/z=510 [M+H]⁺.

[0279] Intermediate 14

4-(4-Fluoro-2-methyl-phenyl)-piperazine-1,3-dicarboxylic acid,3-(S)-tert-butoxycarbonyl-ethyl ester 1-tert-butyl ester(diastereoisomer 2)

[0280] A mixture of intermediate 10b (300 mg), palladium over charcoal(10%-100 mg) and acetic acid (200 μL) in EtOH (20 mL) was hydrogenatedat 6 atm for 16 hours. The catalyst was filtered off and the filtratewas concentrated in vacuo to give14-fluoro-2-methyl-phenyl)-piperazine-1,3-dicarboxylic acid3-(S)-tert-butoxycarbonyl-ethyl ester, (295 mg). Di tert-butyldicarbonate (193 mg) was added to a solution of1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid1-(S)-tert-butoxycarbonyl-ethyl ester (295 mg) and TEA (788 μL) inanhydrous DCM (8 mL), previously cooled to 0° C. under a Nitrogenatmosphere. The solution was allowed to warm to r.t. and stirred at r.t.for 2 hours. The solution was concentrated in vacuo and the residue waspurified by flash chromatography (CH/AcOEt 8:2) to give the titlecompound (195 mg) as white solid.

[0281] T.l.c.: CH/AcOEt 8:2, Rf=0.64.

[0282]¹H-NMR (d₆-DMSO): δ (ppm) 7.17 (dd, 1H); 6.96 (dd, 1H); 6.88 (td,1H); 4.71 (q, 1H); 3.92 (m, 1H); 3.8 (m, 1H); 3.64 (m, 1H); 3.59 (m,1H); 3.42 (m, 1H); 3.3 (m, 1H); 2.7 (m, 1H); 2.27 (s, 3H); 1.41 (s, 9H);1.31 (s, 9H); 1.24 (d, 3H).

[0283] MS (ES/+): m/z=467 [M+H]⁺.

[0284] Intermediate 15

4-(Fluoro-2-methyl-phenyl)-piperazine-1,3-dicarboxylic acid 1-tert-butylester (enantiomer 2)

[0285] A solution of lithium hydroxide monohydrate (70 mg) in water (4mL) was added to a solution of intermediate 14 (190 mg) in MeOH (4 mL)and the resulting solution was heated to 80° C. for 2 hours. The mixturewas concentrated in vacuo to half volume, treated with 5% hydrochloricacid solution until pH=5 and extracted with AcOEt (4×20 mL). The organicphase was dried and concentrated in vacuo to give the title compound(140 mg) as a white solid.

[0286] T.l.c.: CH/AcOEt 1:1 Rf=0.45.

[0287]¹H-NMR (d₆-DMSO): δ (ppm) 12.6 (bs, 1H); 7.14 (dd, 1H); 6.96 (dd,1H); 6.9 (dt, 1H); 3.82-3.72 (bs, 1H); 3.7-3.55 (m, 2H); 3.42-3.34 (m,3H); 2.62 (m, 1H); 2.27 (s, 3H); 1.42 (s, 9H).

[0288] MS (ES/+): m/z=339 [M+H]⁺.

[0289] Intermediate 16

3-[(3,5-Dichloro-benzyl-methylcarbamoyl]-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester (enantiomer 2)

[0290] DIPEA (225 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (175mg) were added to a solution of intermediate 15 (140 mg) in anhydrousDMF (10 mL) under a Nitrogen atmosphere. After stirring for 10 minutes,3,5-dichloro-benzyl-methylamine hydrochloride (103 mg) was added and themixture was stirred at r.t. for 4.5 hours. The solution was diluted withwater (5 mL) and extracted with AcOEt (3×30 mL). The combined organicextracts were washed with brine (3×50 mL), dried and concentrated invacuo to a residue, which was purified by flash chromatography (CH/AcOEt7:3) to give the title compound (180 mg) as a white solid.

[0291] T.l.c.: AcOEt/CH 1:1, Rf=0.7.

[0292]¹H-NMR (d₆-DMSO): δ (ppm) 7.37 (bs, 1H); 7.16 (m, 1H); 6.93 (m,1H); 6.92 (bs, 2H); 6.83 (m, 1H); 4.59 (d, 1H); 4.3-3.2 (bm, 7H); 2.96(bs, 3H); 2.57 (m, 1H); 2.29 (bs, 3H); 1.43 (s, 9H).

[0293] MS (ES/+): m/z=510 [M+H]⁺.

[0294] Intermediate 17

4-Benzyl-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(enantiomer 1)

[0295] A solution of lithium hydroxide monohydrate (43 mg) in water (2mL) was added to a solution of intermediate 10a (121 mg) in MeOH (2 mL)and the resulting solution was heated to 80° C. for 2 hours. The mixturewas concentrated in vacuo to half volume, treated with 5% hydrochloricacid solution until pH=5 and extracted with AcOEt (4×20 mL). The organicphase was dried and concentrated in vacuo to give the title compound(140 mg) as a white solid.

[0296] T.l.c.: CH/AcOEt 1:1 Rf=0.45.

[0297]¹H-NMR (CDCl₃): δ (ppm) 7.3 (m, 5H); 7.0 (m, 1H); 6.8 (m, 2H);3.8-3.6 (m, 5H); 3.2 (m, 1H); 2.9-2.8 (m, 1H); 2.7-2.5 (m, 2H); 2.2 (s,3H).

[0298] Intermediate 18

4-Benzyl-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide (enantiomer 1)

[0299] DIPEA (82 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (63mg) were added to a solution of intermediate 17 (52 mg) in anhydrous DMF(3.5 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,3,5-bis(trifluoromethyl)-benzyl-methylamine hydrochloride (49 mg) wasadded and the mixture was stirred at r.t. for 16 hours. The solution waspartitioned between AcOEt and water. The organic extracts were washedwith water and brine, dried and concentrated in vacuo to a residue whichwas purified by flash chromatography (CH/AcOEt 8:2) to give the titlecompound (56 mg) as yellow oil.

[0300] T.l.c.: AcOEt/CH 1:1, Rf=0.61.

[0301] MS (ES/+): m/z=568 [M+H]⁺.

[0302] Intermediate 19

4-Benzyl-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(enantiomer 2)

[0303] A solution of lithium hydroxide monohydrate (38 mg) in water (2mL) was added to a solution of intermediate 10b (107 mg) in MeOH (2 mL)and the resulting solution was heated to 80° C. for 2 hours. The mixturewas concentrated in vacuo to half volume, treated with 5% hydrochloricacid solution until pH=5 and extracted with AcOEt (4×20 mL). The organicphase was dried and concentrated in vacuo to give the title compound (76mg) as a white solid.

[0304] T.l.c.: CH/AcOEt 1:1 Rf=45.

[0305]¹H-NMR (CDCl₃): δ (ppm) 7.3 (m, 5H); 7.0 (m, 1H); 6.8 (m, 2H); 5.0(bs, 2H); 3.9-3.7 (m, 4H); 3.0-2.8 (m, 1H); 2.8-2.6 (m, 2H); 2.2 (s,3H).

[0306] Intermediate 20

4-Benzyl-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)methylamide (enantiomer 2)

[0307] DIPEA (120 μL) andO(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (93mg) were added to a solution of intermediate 19 (76 mg) in anhydrous DMF(5 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,3,5-bis(trifluoromethyl)-benzyl-methylamine hydrochloride (49 mg) wasadded and the mixture was stirred at r.t. for 16 hours. The solution waspartitioned between AcOEt and water. The organic extracts were washedwith water and brine, dried and concentrated in vacuo to a residue whichwas purified by flash chromatography (CH/AcOEt 8:2) to give the titlecompound (90 mg) as yellow oil. T.l.c.: AcOEt/CH 1:1, Rf=0.61.

[0308]¹H-NMR (d₆-DMSO): δ (ppm) 7.73 (s, 1H); 7.4-7.2 (m, 7H); 7.05 (d,1H); 6.88-6.7 (m, 2H); 4.7-4.3 (m, 2H); 4.28 (dd, 1H); 3.6 (s, 2H); 2.9(s, 3H); 3.1-2.4 (m, 6H); 2.32 (s, 3H).

[0309] Intermediate 21

3-[(3,5-Dibromo-benzyl)-methylcarbamoyl]-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0310] DIPEA (0.34 mL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (257mg) were added to a solution of intermediate 8 (214 mg) in anhydrous DMF(35 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,3,5-dibromo-benzyl-methylamine hydrochloride (300 mg) was added and themixture was stirred at r.t. overnight. The solution was diluted withwater and extracted with AcOEt (3×40 mL). The combined organic extractswere washed with brine, dried and concentrated in vacuo to a residuewhich was purified by flash chromatography (CH/AcOEt 8:2) to give thetitle compound (316 mg) as yellow oil.

[0311] T.l.c.: CH/AcOEt 7:3, Rf=0.51.

[0312]¹H-NMR (d₆-DMSO—90° C.): δ (ppm) 7.66 (bs, 1H); 7.18 (dd, 1H);7.09 (bs, 2H); 6.99 (dd, 1H); 6.88 (m, 1H); 4.8-3.9 (bm, 2H); 4.17 (m,1H); 3.99-3.68 (2bd, 2H); 3.5-3.1 (bm, 3H); 2.94 (s, 3H); 2.52 (bm, 1H);2.3 (s, 3H); 1.42 (bs, 9H).

[0313] MS (ES/+): m/z=598 [M+H]⁺.

[0314] Intermediate 22

3-[(3,4-Dibromo-benzyl)methylcarbamoyl]-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0315] DIPEA (0.1 mL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (74mg) were added to a solution of intermediate 8 (61 mg) in anhydrous DMF(10 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,3,4-dibromo-benzyl-methylamine hydrochloride (85.4 mg) was added and themixture was stirred at r.t overnight The solution was diluted with waterand extracted three times with AcOEt. The combined organic extracts werewashed with brine, dried and concentrated in vacuo to a residue whichwas purified by flash chromatography (CH/AcOEt 7:3) to give the titlecompound (94.1 mg) as yellow oil.

[0316] T.l.c.: CH/AcOEt 7:3, Rf=0.51.

[0317]¹H-NMR (d₆-DMSO—90° C.): δ (ppm) 7.51 (d, 1H); 7.29 (dd, 1H); 7.19(dd, 1H); 7.0 (dd, 1H); 6.9 (m, 1H); 6.65 (bd, 1H); 4.7-4.0 (2bm, 2H);4.15 (m, 1H); 3.88-3.68 (2bd, 2H); 3.6-3.1 (bm, 3H); 2.96 (s, 3H); 2.54(bm, 1H); 2.3 (s, 3H); 1.41 (bs, 9H).

[0318] MS (ES/+): m/z=598 [M+H]⁺.

[0319] Intermediate 23

3-[1-(R)-(3,5-Bis-trifluoromethyl-phenyl)ethyl]-methylcarbamoyl-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester (23a—diastereoisomer 1)3-[1-(R)-(3,5-Bis-trifluoromethyl-phenyl)ethyl]-methylcarbamoyl-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester (23b—diastereoisomer 2)

[0320] DIPEA (238 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (181mg) were added to a solution of intermediate 8 (150 mg) in anhydrous DMF(15 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,1-(R)-[3,5-bis(trifluoromethyl)-phenyl]-ethyl-methylamine hydrochloride(49 mg) was added and the mixture was stirred at r.t. for 5 hours. Thesolution was partitioned between AcOEt and water. The organic extractswere washed with brine, dried and concentrated in vacuo to a residuewhich was purified by flash chromatography (CH/AcOEt 8:2) to give

[0321] intermediate 23a (diastereoisomer 1—35 mg) as yellow oil

[0322] intermediate 23b (diastereoisomer 2—40 mg) as yellow oil.

[0323] Intermediate 23a:

[0324] T.l.c.: AcOEt/CH 1:1, Rf=0.75.

[0325]¹H-NMR (CDCl_(3—50)° C.): δ (ppm) 7.71 (s, 1H); 7.55 (s, 2H); 7.03(m, 1H); 6.9 (dd, 1H); 6.8 (m, 1H); 5.87 (m, 1H); 4.7-3.8 (2m, 3H);3.5-3.2 (m, 3H); 2.74 (s, 3H);2.6 (m, 1H); 2.37 (s, 3H); 1.47 (s, 9H);1.33 (s, 3H).

[0326] MS (ES/+): m/z=592 [M+H]⁺, 614 [M+Na]⁺.

[0327] Intermediate 23b:

[0328] T.l.c.: AcOEt/CH 1:1, Rf=0.71.

[0329] MS (ES/+): m/z=592 M+H]⁺, 614 [M+Na]⁺.

[0330] Intermediate 24

3-(3-Chloro-4-fluoro-benzyl)-methylcarbamoyl-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0331] DIPEA (80 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (60mg) were added to a solution of intermediate 8 (50 mg) in anhydrous DMF(5 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,(3-chloro-4-fluoro-benzyl)-methylamine hydrochloride (32.5 mg) was addedand the mixture was stirred at r.t. overnight. The solution waspartitioned between AcOEt and water. The organic extracts were washedwith brine, dried and concentrated in vacuo to a residue which waspurified by flash chromatography (CH/AcOEt 1:1) to give the titlecompound (43 mg) as yellow oil.

[0332] T.l.c.: AcOEt/CH 1:1, Rf=0.45.

[0333] MS (ES/+): m/z=494 [M+H]⁺.

[0334] Intermediate 25

3-(2,5-Dichloro-benzyl)methylcarbamoyl-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0335] DIPEA (80 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (60mg) were added to a solution of intermediate 8 (50 mg) in anhydrous DMF(5 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,2,5-dichloro-benzyl-methylamine hydrochloride (35 mg) was added and themixture was stirred at r.t. for 5 hours. The solution was partitionedbetween AcOEt and water. The organic extracts were washed with brine,dried and concentrated in vacuo to a residue which was purified by flashchromatography (CH/AcOEt 9:1) to give the title compound (50 mg) asyellow oil.

[0336] T.l.c.: AcOEt/CH 1:1, Rf=0.61.

[0337] MS (ES/+): m/z=510 [M+H]⁺.

[0338] Intermediate 26

3-(3-Fluoro-5-trifluoromethyl-benzyl)-carbamoyl-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0339] DIPEA (80 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (60mg) were added to a solution of intermediate 8 (50 mg) in anhydrous DMF(5 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,(3-fluoro-5-trifluoromethyl)-benzylamine (30 mg) was added and themixture was stirred at r.t. overnight. The solution was partitionedbetween AcOEt and water. The organic extracts were washed with brine,dried and concentrated in vacuo to a residue which was purified by flashchromatography (CH/AcOEt 8:2) to give the title compound (61 mg) asyellow oil.

[0340]¹H-NMR (d₆-DMSO): δ (ppm) 8.3 (t, 1H); 7.43 (d, 1H); 7.19 (s, 1H);7.11 (dd, 1H); 6.94 (dd, 1H); 6.83 (td, 1H); 6.67 (d, 1H); 4.2 (m, 2H);3.94 (m, 1H); 3.74 (d, 1H); 3.67 (dd, 1H); 3.3-3.0 (m, 3H); 2.28 (s,3H); 2.42 (m, 1H); 1.4 (s, 9H).

[0341] MS (ES/+): m/z=514 [M+H]⁺, 536 [M+Na]⁺.

[0342] Intermediate 27

3(3-Fluoro-5-trifluoromethyl-benzyl)methylcarbamoyl-4-(4-fluoro-2-methyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0343] Sodium hydride (60% suspension in mineral oil—7 mg) was added toa solution of intermediate 26 (60 mg) in anhydrous THF (2.5 mL). Thesuspension was stirred at r.t. for 10 minutes, then methyl iodide (22μL) was added. The mixture was heated in a sealed tube at 50° C. for 5hours, adding further sodium hydride (9.4 mg) and methyl iodide (36.4μL) during this time. After cooling to r.t., water was added and themixture was extracted with AcOEt. The organic extract was dried andconcentrated in vacuo to give the title compound (62 mg) as a yellowoil.

[0344] T.l.c.: AcOEt/CH 7:3, Rf=0.54.

[0345] MS (ES/+): m/z=528 [M+H]⁺.

[0346] Intermediate 28

N-Benzyl-2-(2,4-difluoro-phenylamino)-acetamide

[0347] A mixture of N-benzyl-2-chloroacetamide (700 mg—obtained asdescribed for intermediate 1), DIPEA (0.76 mL) and 2,4-difluoro-aniline(0.4 mL) in anhydrous DMF (5 mL) was stirred at 100° C. for 40 hoursunder a Nitrogen atmosphere. Then, more DIPEA (0.2 mL) was added and themixture was heated to 100° C. for further 4 hours. After cooling to roomtemperature, the solution was diluted with AcOEt and washed with waterand ice. The separated aqueous phase was extracted with further AcOEt(3×20 mL). The combined organic extracts were dried and concentrated invacuo. The residue was purified by flash chromatography (CH/AcOEt 7:3)to give the title compound (600 mg) as a beige solid.

[0348] T.l.c.: AcOEt/CH 1:1, Rf=0.39.

[0349]¹H-NMR (d₆-DMSO): δ (ppm) 8.45 (bt, 1H); 7.26 (t, 2H); 7.2 (m,3H); 7.09 (dd, 1H); 6.86 (dd, 1H); 6.52 (td, 1H); 5.68 (bt, 1H); 4.28(d, 2H); 3.73 (d, 2H).

[0350] MS (ES/+): m/z=277 [+H]⁺.

[0351] Intermediate 29

N-Benzyl-N′-(2,4-difluoro-phenyl)-1,2-ethylenediamine

[0352] Borane (1M solution in THF, 17 mL) was added drop-wise at r.t. toa solution of intermediate 28 (586 mg) in anhydrous THF (30 mL) under aNitrogen atmosphere. The mixture was heated to reflux for 4 hours, thenit was cooled to 0° C. and a 10% hydrochloric acid solution (15 mL) wasadded. The mixture was stirred at r.t. overnight. Then, it was basifiedwith solid potassium hydroxide and extracted with AcOEt. The organicphase was washed with water. The aqueous phase was extracted withfurther AcOEt (3×30 mL). The combined organic extracts were concentratedin vacuo to give the title compound (535 mg) as an orange oil.

[0353]¹H-NMR (CDCl₃): δ (ppm) 7.31 (m, 5H); 6.78 (m, 1H); 6.74 (m, 1H);6.61 (m, 1H); 4.2 (bt, 1H); 3.83 (s, 2H); 3.21 (bt, 2H); 2.93 (m, 2H).

[0354] MS (ES/+): m/z=263 [M+H]⁺.

[0355] Intermediates 30

4-Benzyl-1-(2,4-difluoro-phenyl)-piperazine-2-carboxylic acid ethylester

[0356] A solution of intermediate 29 (535 mg) and DIPEA (1.16 mL) intoluene (7 mL) was added to a solution of ethyl 2,3-dibromopropionate(0.6 mL) in toluene (13 mL) previously heated at 50° C. under a Nitrogenatmosphere. The mixture was then stirred at 100° C. for 32 hours. Themixture was cooled to r.t., then diluted with AcOEt and toluene andwashed with water. The separated organic phase was concentrated in vacuoand the residue was purfied by flash chromatography (CH/AcOEt 95:5) togive the title compound (183 mg) as a yellow oil.

[0357] T.l.c.: CH/AcOEt 9:1, Rf=32.

[0358]¹H-NMR (d₆DMSO): δ (ppm) 7.3 (m, 5H); 7.08 (m, 1H); 6.8 (m, 1H);6.76 (m, 1H); 4.21 (m, 1H); 4.07 (m, 2H); 3.81 (dt, 1H); 3.64 (d, 1H);3.46 (d, 1H); 3.23 (m, 1H); 3.0 (m, 1H); 2.89 (m, 1H); 2.56 (dd, 1H);2.43 (dt, 1H); 1.14 (t, 3H).

[0359] MS (ES/+): m/z=361 [M+H]⁺.

[0360] Intermediate 31

1-(2,4-Difluoro-phenyl)-piperazine-2-carboxylic acid ethyl ester

[0361] A mixture of the intermediate 30 (183 mg) in EtOH (20 mL)containing glacial acetic acid (0.2 mL) and 10% palladium on carbon (80mg) was stirred under hydrogen at 5 atm. for 20 hours. The mixture wasfiltered through a pad of celite, and the filtrate was concentrated invacuo to give the title compound (160 mg) as a yellow oil.

[0362]¹H-NMR (CDCl₃): δ (ppm) 7.0 (m, 1H); 6.8 (m, 2H); 4.14 (bs, 1H);4.08 (q, 2H); 3.7-3.5 (m, 2H); 3.45-2.9 (m, 5H); 1.15 (t, 3H).

[0363] MS (ES/+): m/z=271 [M+H]⁺.

[0364] Intermediate 32

4-(2,4-Difluoro-phenyl)-piperazine-1,3-dicarboxylic acid 1-tert-butylester 3-ethyl ester

[0365] Di-tert-butyl-dicarbonate (142 mg) and TEA (0.25 mL) were addedto a solution of intermediate 31 (160 mg) in anhydrous DCM (16 mL) undera Nitrogen atmosphere. The solution was stirred at r.t. for 5 hours,then it was washed with brine. The organic layer was dried andconcentrated in vacuo to give the title compound (155 mg) as a yellowoil.

[0366] T.l.c.: CH/AcOEt 1:1, Rf=0.70.

[0367] MS (ES/+): m/z=371 [M+H]⁺.

[0368] Intermediate 33

4-(2,4-Difluoro-phenyl)-piperazine-1,3-dicarboxylic acid 1-tert-butylester

[0369] A solution of lithium hydroxide hydrate (143 mg) in water (2 mL)was added to a solution of intermediate 32 (1.2 g) in MeOH (16 mL). Themixture was heated to 70° C. for 4 hours. The solution was allowed tocool to r.t., neutralised with 1N hydrochloric acid solution until pH=5and extracted with DCM. The organic layer was dried and concentrated invacuo to give the title compound (120 mg) as pale yellow solid.

[0370] T.l.c.: CH/AcOEt 1:1, Rf=0.19.

[0371]¹H-NMR (CDCl₃): δ (ppm) 7.7 (m, 2H); 7.0 (d, 1H); 4.4 (d, 1H);4.2-3.7 (s+t, 2H); 4.1-3.5 (m+d, 2H); 3.1-2.9 (m+d, 2H); 1.4 (s, 9H).

[0372] Intermediate 34

3-[(3,5-Dichloro-benzyl)-methylcarbamoyl]-4-(2,4-difluoro-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0373] DIPEA (0.113 mL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (75mg) were added to a solution of intermediate 33 (61.5 mg) in anhydrousDMF (7 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,3,5-dichloro-benzyl-methylamine hydrochloride (49.8 mg) was added andthe mixture was stirred at r.t. for 5 hours. The solution waspartitioned between AcOEt and water. The separated aqueous phase wasfurther extracted with AcOEt. The combined organic extracts were washedwith brine, dried and concentrated in vacuo to give the title compound(93 mg) as yellow oil.

[0374] T.l.c.: AcOEt/CH 6:4, Rf=0.89.

[0375] MS (ES/+): m/z=514 M+H]⁺.

[0376] Intermediate 35

3-[(3,5-Bis-trifluoromethyl-benzyl)-methylcarbamoyl]-4-(2,4-difluoro-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0377] DIPEA (0.13 mL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (73mg) were added to a solution of intermediate 33 (60 mg) in anhydrous DMF(7 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,3,5-bis(trifluoromethyl)-benzyl-methylamine hydrochloride (55 mg) wasadded and the mixture was stirred at r.t. for 5 hours. The solution waspartitioned between AcOEt and water. The separated aqueous phase wasfurther extracted with AcOEt. The combined organic extracts were washedwith brine, dried and concentrated in vacuo to give the title compound(115 mg) as yellow oil.

[0378] T.l.c.: AcOEt/CH 6:4, Rf=0.70.

[0379] MS (ES/+): m/z=582 [M+H]⁺.

[0380] Intermediate 36

N-Benzyl-2-(2,4,6-trifluoro-phenylamino)-acetamide

[0381] A mixture of N-benzyl-2-chloroacetamide (700 mg—obtained asdescribed for intermediate 1), DIPEA (0.76 mL) and2,4,6-trifluoro-aniline (559 mg) in anhydrous DMF (5 mL) was stirred at100° C. for 40 hours under a Nitrogen atmosphere. Then, more DIPEA (0.2mL) was added and the mixture was heated to 100° C. for further 4 hours.After cooling to room temperature, the solution was diluted with AcOEtand washed with water and ice. The separated aqueous phase was extractedwith further AcOEt (3×30 mL). The combined organic extracts were driedand concentrated in vacuo. The residue was purified by flashchromatography (CH/AcOEt from 8:2 to 6:4) to give the title compound(265 mg) as a beige solid.

[0382] T.l.c.: AcOEt/CH 1:1, Rf=0.45.

[0383]¹H-NMR (d₆-DMSO): δ (ppm) 7.34-7.29 (m, 5H); 6.9 (bm, 1H); 6.66(m, 2H); 4.53 (d, 2H); 4.0 (bm, 1H); 3.9 (d, 2H).

[0384] MS (ES/+): m/z=295 [M+H]⁺.

[0385] Intermediate 37

N-Benzyl-N′-(2,4,6-trifluoro-phenyl)-1,2-ethylenediamine

[0386] Borane (1M solution in THF, 7.2 mL) was added drop-wise at r.t.to a solution of intermediate 36 (265 mg) in anhydrous THF (13 mL) undera Nitrogen atmosphere. The mixture was heated to reflux for 4 hours,then it was cooled to 0° C. and a 10% hydrochloric acid solution wasadded. The mixture was stirred at r.t. overnight. Then, it was basifiedwith solid potassium hydroxide, diluted with water and extracted withDCM. The organic phase was washed with water. The aqueous phase wasextracted with DCM (3×20 mL). The combined organic extracts wereconcentrated in vacuo to give the tide compound (216 mg) as an orangeoil.

[0387]¹H-NMR (CDCl₃): δ (ppm) 7.28 (m, 4H); 7.2 (m, 1H); 7.03 (t, 2H);4.62 (m, 1H); 3.66 (s, 2H); 3.2 (q, 2H); 2.63 (t, 2H); 2.22 (bs, 1H).

[0388] MS (ES/+): m/z=281 [M+H]⁺.

[0389] Intermediates 38

4-Benzyl-1-(2,4,6-trifluoro-phenyl)-piperazine-2-carboxylic acid ethylester

[0390] A solution of intermediate 37 (216 mg) and DIPEA (0.44 mL) intoluene (2.5 mL) was added to a solution of ethyl 2,3-dibromopropionate(0.22 mL) in toluene (8 mL) previously heated at 50° C. under a Nitrogenatmosphere. The mixture was then stirred at 100° C. for 32 hours. Themixture was cooled to r.t., then diluted with AcOEt and toluene andwashed with water. The separated organic phase was concentrated in vacuoand the residue was purified by flash chromatography (CH/AcOEt 95:5) togive the title compound (57 mg) as a yellow oil.

[0391] T.l.c.: CH/AcOEt 9:1, Rf=0.36.

[0392]¹H-NMR (d₆-DMSO): δ (ppm) 7.31 (m, 5H); 6.61 (m, 2H); 4.11 (m,2H); 4.02 (t, 1H); 3.8 (m, 1H); 3.62 (d, 1H); 3.49 (d, 1H); 3.08 (m,2H); 2.74 (m, 1H); 2.62 (dd, 1H); 2.41 (m, 1H); 1.17 (t, 3H).

[0393] MS (ES/+): m/z=379 [M+H]⁺.

[0394] Intermediate 39

1-(2,4,6-Trifluoro-phenyl)-piperazine-2-carboxylic acid ethyl ester

[0395] A mixture of the intermediate 38 (57 mg) in EtOH (8 mL)containing glacial acetic acid (60 μL) and 10% palladium on carbon (24mg) was stirred underhydrogen at 5 atm. for 20 hours. The mixture wasfiltered through a pad of celite, and the filtrate was concentrated invacuo to give the title compound (53 mg) as a yellow oil.

[0396] T.l.c.: AcOEt/MeOH 8:2, Rf=0.3.

[0397] MS (ES/+): m/z=289 [+H]⁺.

[0398] Intermediate 40

4-(2,4,6-Trifluoro-phenyl)-piperazine-1,3-dicarboxylic acid 1-tert-butylester 3-ethyl ester

[0399] Di-tert-butyl-dicarbonate (44 mg) and TEA (77 μL) were added to asolution of intermediate 39 (53 mg) in anhydrous DCM (5 mL) under aNitrogen atmosphere. The solution was stirred at r.t. for 5 hours, thenit was washed with brine. The organic layer was dried and concentratedin vacuo to give the title compound (67 mg) as a yellow oil.

[0400] T.l.c.: CH/AcOEt 1:1, Rf=0.75.

[0401] Intermediate 41

4-(2,4,6-Trifluoro-phenyl)-piperazine-1,3-dicarboxylic acid 1-tert-butylester

[0402] A solution of lithium hydroxide hydrate (43 mg) in water (0.5 mL)was added to a solution of intermediate 40 (67 mg) in MeOH (4 mL). Themixture was heated to 70° C. for 4 hours. The solution was allowed tocool to r.t., neutralised with 1N hydrochloric acid solution until pH=5and extracted with DCM. The organic layer was dried and concentrated invacuo to give the title compound (50 mg) as pale yellow solid.

[0403] T.l.c.: CH/AcOEt 1:1, Rf=0.2.

[0404] Intermediate 42

3-[(3,5-Dichloro-benzyl)-methylcarbamoyl]-4-(2,4,6-trifluoro-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0405] DIPEA (38 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (29mg) were added to a solution of intermediate 41 (25 mg) in anhydrous DMF(3 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,3,5-dichloro-benzyl-methylamine hydrochloride (18 mg) was added and themixture was stirred at r.t. for 5 hours. The solution was partitionedbetween AcOEt and water. The separated aqueous phase was furtherextracted with AcOEt The combined organic extracts were washed withbrine, dried and concentrated in vacuo to give the title compound (25mg) as yellow oil.

[0406] T.l.c.: AcOEt/CH 1:1, Rf=0.89.

[0407] Intermediate 43

3-[(3,5-Bis-trifluoromethyl-benzyl)-methylcarbamoyl]-4-(2,4,6-trifluoro-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0408] DIPEA (38 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (29mg) were added to a solution of intermediate 41 (25 mg) in anhydrous DMF(3 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,3,5-(bis-trifluoromethyl)-benzyl-methylamine hydrochloride (18 mg) wasadded and the mixture was stirred at r.t. for 5 hours. The solution waspartitioned between AcOEt and water. The separated aqueous phase wasfurther extracted with AcOEt. The combined organic extracts were washedwith brine, dried and concentrated in vacuo to give the title compound(31 mg) as yellow oil.

[0409] T.l.c.: AcOEt/CH 1:1, Rf=0.8.

[0410] Intermediate 44

N-Benzyl-2-(4-fluoro-phenylamino)-acetamide

[0411] A mixture of N-benzyl-2-chloroacetamide (8.3 g—obtained asdescribed for intermediate 1), DIPEA (9.31 mL) and 4-fluoro-aniline(4.28 mL) in anhydrous DMF (60 mL) was stirred at 100° C. for 24 hoursunder a Nitrogen atmosphere and then left at r.t. for two days. Thesolution was poured into water (100 mL) and extracted with AcOEt (2×200mL). The combined organic extracts were washed with brine (100 mL),dried and concentrated in vacuo. The residue was purified by flashchromatography (CH/AcOEt 7:3) to give the title compound (7.73 g) as abeige solid.

[0412]¹H-NMR (CDCl₃): δ (ppm) 7.2 (m, 5H); 7.0 (bs, 1H); 6.8 (t, 2H);6.5 (dd, 2H); 4.4 (d, 2H); 4.2 (bs, 1H); 3.8 (d, 2H).

[0413] Intermediate 45

N-Benzyl-N′-(4-fluoro-phenyl)-1,2-ethylenediamine

[0414] Borane (1M solution in THF, 112 mL) was added drop-wise at r.t.to a solution of intermediate 44 (3.7 g) in anhydrous THF (200 mL) undera Nitrogen atmosphere. The mixture was heated to reflux for 4 hours,then it was cooled to 0° C. and a 10% hydrochloric acid solution (50 mL)was added. The mixture was stirred at r.t. for 8 hours. Then, it wasextracted three times with AcOEt The combined organic extracts weredried and concentrated in vacuo. The residue was diluted with water andbasified with solid potassium hydroxide. The solution was with DCM. Thecombined organic extracts were concentrated in vacuo to give the titlecompound (2.84 g) as an orange oil.

[0415]¹H-NMR (CDCl₃): δ (ppm) 7.3 (m, 5H); 6.8 (t, 2H); 6.5 (dd, 2H);3.8 (s, 2H); 3.2 (t, 2H); 2.8 (t, 2H).

[0416] Intermediates 46

4-Benzyl-1-(4-fluoro-phenyl)-piperazine-2-carboxylic acid ethyl ester

[0417] A solution of intermediate 45 (2.81 g) and DIPEA (6.59 mL) intoluene (40 mL) and DMF (5 mL) was added to a solution of ethyl2,3-dibromopropionate (3.34 mL) in toluene (70 mL) previously heated at50° C. under a Nitrogen atmosphere. The mixture was then stirred at 100°C. for 22 hours. The mixture was cooled to r.t., then diluted with AcOEtand toluene and washed with water. The separated organic phase wasconcentrated in vacuo and the residue was purified by flashchromatography (CH/AcOEt 95:5) to give the title compound (1.18 g) as ayellow oil.

[0418] T.l.c.: CH/AcOEt 95:5, Rf=0.62.

[0419]¹H-NMR (d₆-DMSO): δ (ppm) 7.31-7.27 (m, 5H); 6.94 (m, 2H); 6.81(m, 2H); 4.33 (m, 1H); 4.08 (m, 2H); 3.65 (d, 1H); 3.59 (td, 1H); 3.45(d, 1H); 3.29 (m, 2H); 2.95 (m, 1H); 2.47 (dd, 1H); 2.37 (dt, 1H); 1.12(t, 3H).

[0420] MS (ES/+): m/z=343 [M+H]⁺.

[0421] Intermediate 47

4-Benzyl-1-(4-fluoro-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl-methylamide

[0422] Lithium hydroxide hydrate (46 mg) was added to a solution ofintermediate 46 (94 mg) in MeOH (8 mL) and water (1 mL) and theresulting solution was stirred at 70° C. for 5 hours. The solution wasallowed to cool to r.t., neutralized with 1N hydrochloric acid andextracted with DCM and AcOEt. The combined organic extracts were driedand concentrated in vacuo to give4-benzyl-1-(4-fluoro-phenyl)-piperazine-2-carboxylic acid (88 mg) whichwas used for the next step without any purification.

[0423] DIPEA (147 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (112mg) were added to a solution of4-benzyl-1-(4-fluoro-phenyl)-piperazine-2-carboxylic acid (88 mg) inanhydrous DMF (10 mL) under a Nitrogen atmosphere. After stirring for 5minutes, 3,5-bis(trifluoromethyl)-benzyl-methylamine hydrochloride (85mg) was added and the mixture was stirred at r.t over week end. Thesolution was diluted with water and extracted twice with AcOEt. Thecombined organic extracts were washed with brine, dried and concentratedin vacuo to a residue which was purified by flash chromatography(CH/AcOEt 7:3) to give the title compound (77 mg) as yellow oil.

[0424] T.l.c.: AcOEt/CH 6:4, Rf=0.57.

[0425] IR (film, cm⁻¹): 1652 (C═O).

[0426]¹H-NMR (d₆-DMSO): δ (ppm) 7.98 (s, 1H); 7.76 (s, 2H); 7.35-7.2 (m,5H); 6.93 (m, 2H); 6.83 (m, 2H); 4.9 (bs, 1H); 4.83 (d, 1H); 4.34 (d,1H); 3.68 (m, 1H); 3.58 (d, 1H) 3.47 (d, 1H); 3.28 (m, 1H); 3.04 (m,1H); 2.86 (m, 1H); 2.91 (s, 3H); 2.43 (dd, 1H); 2.25 (td, 1H).

[0427] MS (ES/+): m/z=554 [M+H]⁺.

[0428] Intermediate 48

1-(4-Fluoro-phenyl)-piperazine-2-carboxylic acid ethyl ester

[0429] A mixture of the intermediate 46 (1.09 g) in EtOH (100 mL)containing glacial acetic acid (1 mL) and 10% palladium on carbon (400mg) was stirred under hydrogen at 5 atmospheres for 19 hours. Themixture was filtered through a pad of celite, and the filtrate wasconcentrated in vacua. The crude was dissolved in AcOEt and washed witha 5% sodium hydrogen carbonate solution. the organic layer was dried andconcentrated in vacuo to give the title compound (651 mg) as a yellowoil.

[0430] T.l.c.: AcOEt/MeOH 8:2, Rf=0.16.

[0431]¹H-NMR (CDCl₃): δ (ppm) 7.0 (m, 2H); 6.9 (m, 2H); 4.3 (s, 1H); 4.2(q, 2H); 3.4 (m, 2H); 3.2-3.0 (2m, 4H); 1.2 (t, 3H).

[0432] Intermediate 49

4-(4-Fluoro-phenyl)-piperazine-1,3-dicarboxylic acid 1-tert-butyl ester3-ethyl ester

[0433] Di-tert-butyl-dicarbonate (457 mg) and TEA (663 μL) were added toa solution of intermediate 48 (651 mg) in anhydrous DCM (30 mL) under aNitrogen atmosphere. The solution was stirred at r.t. for 24 hours, thenfurther di-tert-butyl-dicarbonate (207 mg) and TEA (265 μL) were added.The solution was stirred for further 24 hours, then it was washed withwater. The organic layer was dried and concentrated in vacuo to a crude,which was purified by flash chromatography (CH/AcOEt 7:3) to give thetitle compound (908 mg) as a yellow oil.

[0434] T.l.c.: AcOEt/MeOH 8:2, Rf=0.89.

[0435]¹H-NMR (CDCl₃): δ (ppm) 6.9 (m, 2H); 6.8 (m, 2H); 4.4 (d, 1H);4.2-4.0 (m, 2H); 4.0 (m, 2H); 3.6-3.2 (m, 2H); 3.2-3.0 (m, 2H); 1.4 (s,9H); 1.2 (t, 3H).

[0436] MS (ES/+): m/z=353 M+H]⁺.

[0437] Intermediate 50

4-(4-Fluoro-phenyl)-piperazine-1,3-dicarboxylic acid 1-tert-butyl ester

[0438] A solution of lithium hydroxide hydrate (537 mg) was added to asolution of intermediate 49 (750 mg) in MeOH (48 mL) and water (8 mL).The mixture was heated to 80° C. for 4 hours. The solution was allowedto cool to r.t., neutralised with 1N hydrochloric acid solution untilpH=7 and extracted with AcOEt. The organic layer was dried andconcentrated in vacuo to give the title compound (610 mg) as pale yellowsolid.

[0439]¹H-NMR (CDCl₃): δ (ppm) 7.0 (t, 2H); 6.8 (dd, 2H); 4.4-4.2 (m,2H); 4.0 (m, 1H); 3.5-3.2 (m, 4H); 1.4 (s, 9H).

[0440] Intermediate 51

3-[(3,5-Dichloro-benzyl)methylcarbamoyl]-4-(4-fluoro-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0441] DIPEA (116 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (104mg) were added to a solution of intermediate 50 (70 mg) in anhydrous DMF(15 mL) under a Nitrogen atmosphere. After stirring for 5 minutes,3,5-dichloro-benzyl-methylamine hydrochloride (73 mg) was added and themixture was stirred at r.t. overnight. The solution was partitionedbetween AcOEt and water. The separated aqueous phase was furtherextracted with AcOEt. The combined organic extracts were washed withbrine, dried and concentrated in vacuo to a crude, which was purified byflash chromatography (CH/AcOEt 1:1) to give the title compound (65 mg)as yellow oil.

[0442] T.l.c.: AcOEt/CH 1:1, Rf=0.61.

[0443] MS (ES/+): m/z=97 M+H]⁺.

[0444] Intermediate 52

N-Benzyl-2-(4-triluoromethyl-phenylamino)-acetamide

[0445] A mixture of N-benzyl-2-chloroacetamide (0.7 g—obtained asdescribed for intermediate 1), DIPEA (0.78 mL) and4-trifluoromethyl-aniline (0.48 mL) in anhydrous DMF (7 mL) was stirredat 100° C. for 70 hours under a Nitrogen atmosphere. The solution waspoured into water and extracted twice with AcOEt. The combined organicextracts were washed with brine, dried and concentrated in vacuo. Theresidue was purified by flash chromatography (CH/AcOEt 7:3) to give thetitle compound (1.85 g).

[0446]¹H-NMR (CDCl₃): δ (ppm) 7.45-7.4 (d, 2H); 7.3-7.15 (m, 5H); 6.7(bm, 1H); 6.6 (d, 2H); 4.6 (bm, 1H); 4.45 (d, 2H); 3.85 (d, 2H).

[0447] Intermediate 53

N-Benzyl-N′-(4-trifluoromethyl-phenyl)-1,2-ethylenediamine

[0448] Borane (1M solution in THF, 14.9 mL) was added dropwise at r.t.to a solution of intermediate 52 (0.57 g) in anhydrous THF (24 mL) undera Nitrogen atmosphere. The mixture was heated to reflux for 3 hours,then it was cooled to 0° C. and a 10% hydrochloric acid solution wasadded. The mixture was stirred at r.t. for overnight. Then, it wasextracted three times with AcOEt. The combined organic extracts weredried and concentrated in vacuo. The residue was diluted with water andbasified with solid potassium hydroxide. The solution was extractedtwice with DCM. The combined organic extracts were concentrated in vacuoto give the title compound (0.45 g) as a yellow oil.

[0449]¹H-NMR (CDCl₃): δ (ppm) 7.45-7.25 (m, 7H); 6.68 (d, 2H); 4.55 (bm,1H); 3.75 (s, 2H); 3.21 (q, 2H); 2.92 (m, 2H).

[0450] MS (ES/+): m/z=295 [+H]⁺.

[0451] Intermediate 54

4-Benzyl-1-(4-trifluoromethyl-phenyl)-piperazine-2-carboxylic acid ethylester

[0452] A solution of intermediate 53 (0.43 g) and DIPEA (0.84 mL) intoluene (4 mL) was added to a solution of ethyl 2,3-dibromopropionate(0.425 mL) in toluene (10 mL) previously heated to 50° C. under aNitrogen atmosphere. The mixture was then stirred at 100° C. for 40hours. The mixture was cooled to r.t., then diluted with AcOEt andtoluene and washed with water. The separated organic phase wasconcentrated in vacuo and the residue was purified by flashchromatography (CH/AcOEt 95:5) to give the title compound (183 mg).

[0453] T.l.c.: CH/AcOEt 9:1, Rf=0.30.

[0454]¹H-NMR (d₆-DMSO): δ (ppm) 7.45 (d, 2H); 7.35-7.26 (m, 5H); 6.84(d, 2H); 4.47 (t, 1H); 4.11 (m, 2H); 3.65 (d, 1H); 3.53 (m, 2H); 3.45(d, 1H); 3.37 (m, 1H); 3.0 (m, 1H); 2.41 (dd, 1H); 2.32 (m, 1H); 1.13(t, 3H).

[0455] MS (ES/+): m/z=393 [M+H]⁺.

[0456] Intermediate 55

1-(4-Trifluoromethyl-phenyl)-piperazine-2-carboxylic acid ethyl ester

[0457] A mixture of the intermediate 54 (180 mg) in EtOH (16.7 mL)containing glacial acetic acid (0.17 mL) and 10% palladium on carbon (67mg) was stirred under hydrogen at 5 atmospheres for 20 hours. Themixture was filtered through a pad of celite, and the filtrate wasconcentrated in vacuo to give the title compound (163 mg).

[0458] T.l.c.: AcOEt/MeOH 8:2, Rf=0.44.

[0459] MS (ES/+): m/z=303 M+H]⁺.

[0460] Intermediate 56

4-(4-Trifluoromethyl-phenyl)-piperazine-1,3-dicarboxylic acid1-tert-butyl ester 3-ethyl ester

[0461] Di-tert-butyl-dicarbonate (127 mg) and TEA (185 μL) were added toa solution of intermediate 55 (160 mg) in anhydrous DCM (14 mL) under aNitrogen atmosphere. The solution was stirred at r.t. for 3 hours, thenit was concentrated in vacuo to a crude, which was purified by flashchromatography (CH/AcOEt 6:4) to give the title compound (280 mg).

[0462] T.l.c.: AcOEt/CH 8:2, Rf=0.90.

[0463]¹H-NMR (d₆-DMSO): δ (ppm) 7.45 (d, 2H); 6.85 (d, 2H); 4.6 (bd,1H); 4.4 (s, 1H); 4.2-4.05 (bm, 3H); 3.53 (bm, 2H); 3.3 (bd, 1H); 3.1(m, 1H); 1.5 (s, 9H); 1.2 (t, 3H).

[0464] MS (ES/+): m/z=425 [M+Na]⁺.

[0465] Intermediate 57

4-(4-Trifluoromethyl-phenyl)-piperazine-1,3-dicarboxylic acid1-tert-butyl ester

[0466] A solution of lithium hydroxide hydrate (175 mg) was added to asolution of intermediate 56 (750 mg) in MeOH (14 mL) and water (3 mL).The mixture was heated to 80° C. for 2 hours. The solution was allowedto cool to r.t, neutralised with 1N hydrochloric acid solution untilpH=7 and extracted with DCM. The organic layer was dried andconcentrated in vacuo to give the title compound (125 mg).

[0467]¹H-NMR (CDCl₃): δ (ppm) 7.45 (d, 2H); 6.8 (m, 2H); 4.55 (d, 1H);4.3 (bm, 1H); 4.05 (bm, 1H); 3.45 (bm, 2H); 2.9 (bm, 2H); 1.37 (s, 9H).

[0468] MS (ES/+): m/z=397 [M+Na]⁺.

[0469] Intermediate 58

3-[(3,5-Dichloro-benzyl)-methylcarbamoyl]-4-(4-trifluoromethyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0470] DIPEA (84 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (67mg) were added to a solution of intermediate 57 (60 mg) in anhydrous DMF(7 mL) under a Nitrogen atmosphere. After stirring for 1 hour,3,5-dichloro-benzyl-methylamine hydrochloride (40 mg) was added and themixture was stirred at r.t. for 3 hours. The solution was partitionedbetween AcOEt and water. The organic extracts was washed with brine,dried and concentrated in vacuo to a crude, which was purified by flashchromatography (CH/AcOEt 7:3) to give the title compound (61 mg).

[0471]¹H-NMR (CDCl₃): δ (ppm) 7.45 (d, 2H); 7.2 (d, 1H); 7.0 (bs, 2H);6.75 (m, 2H); 4.65 (bm, 2H); 4.4-4.15 (bq, 2H); 4.05 (bm, 1H); 3.9 (bm,1H); 3.45 (bm, 2H); 3,25 (bt, 1H); 3.05 (s, 3H); 1.45 (s, 9H).

[0472] Intermediate 59

3-[(3,5-Bis-trifluoromethyl-benzyl)-methylcarbamoyl]-4-(4-trifinoromethyl-phenyl)-piperazine-1-carboxylicacid tert-butyl ester

[0473] DIPEA (84 μL) andO-(benzotriazol-1-yl)-N,N,N′N′-tetramethyluronium tetrafluoroborate (67mg) were added to a solution of intermediate 57 (60 mg) in anhydrous DMF(7 mL) under a Nitrogen atmosphere. After stirring for 1 hour,3,5-(bis-trifluoromethyl)-benzyl-methylamine hydrochloride (52 mg) wasadded and the mixture was stirred at r.t for 20 hours. The solution waspartitioned between AcOEt and water. The organic extracts was washedwith brine, dried and concentrated in vacuo to a crude, which waspurified by flash chromatography (CH/AcOEt 7:3) to give the titlecompound (70 mg).

[0474]¹H-NMR (CDCl₃): δ (ppm) 7.75 (s, 1H); 7.6 (bm, 2H); 7.45 (d, 2H);6.75 (m, 2H); 4.85 (bm, 1H); 4.75 (bm, 2H); 4.5-4.2 (bm, 2H); 4.05 (bm,1H); 3.6 (bm, 1H); 3,25 (bt, 1H); 3.1 (s, 3H); 1.45 (s, 9H).

[0475] MS (ES/+): m/z=636 [M+Na]⁺.

[0476] Intermediate 60

2(4-Fluoro-2-methyl-phenylamino)-ethanol hydrochloride

[0477] In a glass round bottom flask 4-fluoro-2-methylaniline (1 g),2-chloroethanol (0.64 mL) and DIPEA (1.67 mL) were added. Thehomogeneous mixture was heated to 125-130° C. for 6-10 hours. Then itwas cooled to 60° C. and it was diluted with AcOEt (7 mL). The mixturewas cooled to 15-20° C. and left overnight without stirring.

[0478] The following day, stirring the mixture at 20° C., a solution of6N hydrochloric acid solution in isopropanol (2.5 mL) was dropped over20 minutes. After a while a solid precipitates and it was stirred for 2hours at 20° C. Then it was filtered and washed with AcOEt (3.5 mL) anddried at 40° C. for 18 hours to give the title compound as a white solid(1.07 g).

[0479]¹H-NMR (d₆-DMSO): δ (ppm) 11.0-7.0 (bs, 2-3H); 7.41 (bm, 1H); 7.18(dd, 1H);7.12 (dt, 1H); 3.68 (t, 2H); 3.25 (t, 2H); 2.38 (s, 3H).

[0480] Intermediate 61

3′,5′-Dichloroacetophenone

[0481] A solution of methyl iodide (4 mL) in anhydrous Et2O (40 mL) wasdropped into a suspension of magnesium (1.6 g) in anhydrous Et2O (16 mL)under a Nitrogen atmosphere. At the end of the dropping, benzene (120mL) was added and the Et2O eliminated with a Nitrogen flux. Then, asolution of 3,5-dichlorobenzonitrile (4 g) in benzene (48 mL) was addedand the mixture was heated to reflux for 3 hours. The solution wascooled to 0° C. and a 6N hydrochloric acid solution was added and themixture was stirred overnight at r.t. Water and Et2O were added and thelayers were separated. The organic phase was washed with a saturatedsodium hydrogen carbonate solution and brine, dried and concentrated invacuo. The residue was purified by flash chromatography (CH/AcOEt 95:5)to give the title compound (2.55 g) as an orange oil.

[0482] T.l.c.: CH/AcOEt 8:2, Rf=0.64.

[0483] NMR (CDCl₃): δ (ppm) 7.75 (s, 2H); 7.6 (s, 1H); 2.55 (s, 3H).

[0484] Intermediate 62

1-(3,5-Dichloro-phenyl)-ethyl]-methylamine

[0485] Methylamine (2M solution in MeOH—13 mL) was added to a solutionof intermediate 61 (500 mg) in MeOH (26 mL) under a Nitrogen atmosphere.The mixture was stirred at r.t. for 18 hours, then it was cooled to 0°C. and sodium borohydride (98 mg) was added. The mixture was stirred at0° C. for 2 hours, then it was quenched with water and extracted withDCM. The organic layer was dried and concentrated in vacuo to give thetitle compound (340 mg) as yellow oil.

[0486] T.l.c.: CH/AcOEt 1:1, Rf=0.15.

[0487] NMR (CDCl₃): δ (ppm) 7.3 (m, 3H); 3.6 (q, 1H); 2.3 (s, 3H); 1.35(d, 3H).

[0488] MS (ES/+): m/z=204 [M+H]⁺.

EXAMPLE 1 (±) 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3.5-bis-trifluoromethyl-benzyl)methylamide hydrochloride

[0489] A mixture of intermediate 5 (0.7 g) in EtOH (85 mL) containingglacial acetic acid (0.28 mL) and 10% palladium on carbon (0.155 g) wasstirred under hydrogen at 70 p.s.i. for 22 hours. The mixture wasfiltered through a pad of celite and the pad washed with further EtOH(50 mL). Concentration in vacuo gave a crude which was purified by flashchromatography (DCM/EtOH/NH₄OH from 100:8:1 to 75:8:1 to give1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide (Q.5 g) as a yellow gum(T.l.c.: AcOEt/MeOH 8:2, Rf=0.18).

[0490] This material (91 mg) was dissolved in anhydrous Et2O (1.5 mL)and treated at 0° C. with hydrochloric acid (1M in Et2O—0.25 mL). Themixture was stirred at 0° C. for 15 minutes, then concentrated in vacuo.The residue was washed with pentane (2×4 mL) to give the title compound(90 mg) as a whitish solid.

[0491] M.p.: 85-90° C.

[0492] IR (film, cm⁻¹): 3404 (NH), 1641 (C═O).

[0493]¹H-NMR (d₆-DMSO): δ (ppm) 7.89 (s, 1H); 7.54 (s, 2H); 7.09 (dd,1H); 6.88 (dd, 1H); 6.72 (td, 1H); 4.7-4.5 (m, 1H); 4.4-4.2 (m, 2H);3.04 (s, 3H); 2.82 (bd, 1H); 2.6 (m, 3H); 2.28 (m, 2H); 2.23 (s, 3H);2.2 (s, 3H).

[0494] MS (ES/+): m/z=478 [M-HCl+H]⁺.

EXAMPLE 2 (±)-1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide hydrochloride

[0495] Method A:

[0496] TFA (1.5 mL) was dropped into a solution of intermediate 9 (65mg) in dry DCM (5 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 2.5 hours, thenconcentrated in vacuo. The residue was purified by flash chromatography(DCM/MeOH 95:5) to give1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide (25 mg) as a colourless oil.

[0497] T.l.c.: DCM/MeOH 9:1, Rf=0.2.

[0498] This material (25 mg) was dissolved in anhydrous Et2O (2 mL) andtreated at 0° C. with hydrochloric acid (1M in Et2O—73 □L). The mixturewas stirred at 0° C. for 30 minutes, then concentrated in vacuo. Theresidue was washed with pentane to give the title compound (15 mg) as anoff-white solid.

[0499]¹H-NMR (d₆-DMSO): δ (ppm) 9.21 (bs, 1H); 8.62 (bs, 1H); 7.44 (bs,1H); 7.05 (m, 3H); 6.88 (m, 2H); 4.61 (d, 1H); 4.55 (bt, 1H); 4.19 (d,1H); 3.7-2.97 (bm, 6H); 2.67 (s, 3H); 2.33 (s, 3H).

[0500] MS (ES/+): m/z=410 [M+H—HCl]⁺.

[0501] Method B

[0502] The compound of Example 2a (700 mg) was dissolved in anhydrousEt2O (15 mL) and treated at 0° C. with hydrochloric acid (1M inEt2O—1.87 mL). The mixture was stirred at 0° C. for 30 minutes, thenconcentrated in vacuo. The residue was triturated with pentane (3×5 mL)to give the title compound (735 mg) as an off-white solid.

[0503] M.p.: 110-113° C.

[0504]¹H-NMR (d₆-DMSO): δ (ppm) 9.21 (bs, 1H); 8.62 (bs, 1H); 7.44 (bs,1H); 7.05 (m, 3H); 6.88 (m, 2H); 4.61 (d, 1H); 4.55 (bt, 1H); 4.19 (d,1H); 3.7-2.97 (bm, 6H); 2.67 (s, 3H); 2.33 (s, 3H).

EXAMPLE 2a (±) 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylicacid, (3,5-dichloro-benzyl)-methylamide

[0505] Method A

[0506] TFA (20 mL) was dropped into a solution of intermediate 9 (3.14g) in dry DCM (80 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 5 hours, thenconcentrated in vacuo. The residue was diluted with AcOEt (100 mL) andwashed with a saturated sodium carbonate solution (4×60 mL) and brine(50 mL). The organic layer was concentrated in vacuo. The residue wastriturated with Et2O (2×10 mL) to give the title compound (2.1 g) as awhite solid. Concentration in vacuo of the organic phase followed bypurification of the residue by flash chromatography (DCM/MeOH 95:5) gavea further amount (82 mg) of the title compound.

[0507] Method B

[0508] DIPEA (0.48 mL) was added to the solution of intermediate 9a inAcOEt (6 mL) at room temperature. To the mixture 1-chloroethylchloroformiate (0.44 mL) was dropped over 15 minutes. The resultingsolution was stirred at room temperature over 2 hours then 1Nhydrochloric acid (5.5 mL) was added and the reaction was heated at 60°C. for 2 hours. The organic mixture was cooled to room temperature thenisooctane (10 mL) and MeOH (2 mL) were added.

[0509] The the two phases were separated and the aqueous one was washedagain with isooctane/AcOEt 2/1(8 mL).

[0510] To the aqueous layer AcOEt (10 mL) was added and under a vigorousstirring a 10% ammonium hydroxide solution (6 mL) was dropped. The pH ofthe solution was check (it should be more than 8) The two phases wereseparated and the organic layer was washed with water (2×5 mL). Theorganic layer was concentrated to 7 vol and then diluted again withAcOEt (7 mL) and finally concentrated to 7 mL. The solid was thenprecipitated by isooctane (7 mL) addition. The solid was stirredovernight at room temperature. It was filtered and washed with a 1/1isooctane/AcOEt mixture (3 mL).After drying into an oven at 40° C., thetitle compound (0.47 g) was obtained.

[0511] T.l.c.: DCM/MeOH 9:1, Rf=0.2.

[0512] M.p.: 161-2° C.

[0513]¹H-NMR (d₆-DMSO): δ (ppm) 7.4 (s, 1H); 7.08 (m, 1H); 6.97 (m, 1H);6.83 (m, 1H); 6.82 (s, 2H); 4.75 (d, 1H); 4.6-3.96 (m, 2H); 3.1-2.7 (m,2H); 2.67 (s, 3H); 2.8-2.2 (m, 3H).

EXAMPLE 3 (+)-1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide hydrochloride

[0514] Method A

[0515] TFA (0.8 mL) was dropped into a solution of intermediate 13 (167mg) in dry DCM (4 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 3 hours, thenconcentrated in vacuo. The residue was dissolved in AcOEt and washedwith 10% sodium carbonate solution, dried and concentrated in vacuo. Theresidue was purified by flash chromatography (DCM/MeOH 9:1) to give(+)-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide (120 mg) as a white solid (T.l.c.:DCM/MeOH 9:1, Rf=0.2).

[0516] This material (120 mg) was dissolved in anhydrous Et2O (3 mL) andtreated at −5° C. with hydrochloric acid (1M in Et2O—0.33 mL). Themixture was stirred at −5° C. for 30 minutes, then concentrated invacuo. The residue was washed with pentane to give the title compound(122 mg) as a white solid.

[0517] SFC: column Chirapack AD 25 cm×4.6 mm, column temperature 35° C.,mobile phase CO2/EtOH (+0.15 isopropanol) 65:35, flow 2.5 mL/min, columnpressure 180 bar; detector UV-MS, λ=225 nm; retention time 2.28 minutesm/z=410 M+H]⁺, 87% a/a).

[0518] Method B

[0519] The compound of Example 5a (233 mg) was dissolved in anhydrousEt2O (10 mL) and treated at 0° C. with hydrochloric acid (1M inEt2O—0.62 mL). The mixture was stirred at 0° C. for 30 minutes, thenconcentrated in vacuo. The residue was washed with pentane (3×2 mL) togive the title compound (249 mg) as an off-white solid.

[0520]¹H-NMR (d₆-DMSO): δ (ppm) 9.21 (bs, 1H); 8.62 (bs, 1H); 7.44 (bs,1H); 7.05 (m, 3H); 6.88 (m, 2H); 4.61 (d, 1H); 4.55 (bt, 1H); 4.19 (d,1H); 3.7-2.97 (bm, 6H); 2.67 (s, 3H); 2.33 (s, 3H).

[0521] MS (ES/+): m/z=410 [M+H—HCl]⁺.

[0522] [α]_(D)=+25.3 (c=0.49% w/v in DMSO)

EXAMPLE 4 (−)-1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide hydrochloride (enantiomer 2)

[0523] Method A

[0524] TFA (1 mL) was dropped into a solution of intermediate 16 (170mg) in dry DCM (5 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 2 hours, thenconcentrated in vacuo. The residue was dissolved in AcOEt (20 mL) andwashed with water (5 mL) and a saturated solution of potassium carbonate(10 mL). The organic layer was dried and concentrated in vacuo. Theresidue was purified by flash chromatography (DCM/MeOH 9:1) to give(−)-1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide (120 mg) as a white solid (T.l.c.:DCM/MeOH 9:1, Rf=0.2).

[0525] This material (120 mg) was dissolved in anhydrous Et2O (5 mL) andAcOEt (1 mL) and treated at −5° C. with hydrochloric acid (1M inEt2O—0.323 mL). The mixture was stirred at −5° C. for 30 minutes, thenconcentrated in vacuo. The residue was washed with pentane (3×2 mL) togive the title compound (115 mg) as a white solid.

[0526] SFC: column Chirapack AD 25 cm×4.6 mm, column temperature 35° C.,mobile phase CO2/EtOH (+0.15 isopropanol) 65:35, flow 2.5 mL/min, columnpressure 180 bar; detector UV-MS, λ=225 nm; retention time 4.61 minutes;82% a/a).

[0527] Method B

[0528] The compound of Example 5b (192 mg) was dissolved in anhydrousEt2O (10 mL) and treated at 0° C. with hydrochloric acid (1M inEt2O—0.515 mL). The mixture was stirred at 0° C. for 30 minutes, thenconcentrated in vacuo. The residue was washed with pentane (2×2 mL) togive the title compound (200 mg) as an off-white solid.

[0529]¹H-NMR (d₆-DMSO): δ (ppm) 9.35 (bs, 1H); 8.7 (bs, 1H); 7.42 (s,1H); 7.04 (s, 2H); 7.1-6.8 (m, 3H); 4.6 (d, 1H); 4.57 (m, 1H); 4.16 (d,1H); 3.6-2.98 (bm, 6H); 2.68 (s, 3H); 2.31 (s, 3H).

[0530] MS (ES/+): m/z=410 [M+H—HCl]⁺.

[0531] [α]_(D)=−4.6 (c=0.52% w/v in DMSO—not clear solution)

EXAMPLE 4a Example 3 and example 4 as 75:25 mixture

[0532] Example 3 (75.5 mg) and example 4 (25.6 mg) were mixed to giveenriched mixtures 75:25 to give the title compound.

[0533] HPLC: column Chirapack AD 25 cm×4.6 mm×5 μm, mobile phasen-hexane/EtOH 80:20, flow 7 ml/min; detector DAD, λ=220-360 nm, scanrange 150-1000; ionisation method ES/+; retention time 6.72 minutes(enantiomer 1; 75.6% a/a) and 8.91 minutes (enantiomer 2; 24.4% a/a).

EXAMPLE 4b Example 3 and example 4 as 25:75 mixture

[0534] Example 3(25.2 mg) and Example 4(75.2 mg) were mixed to giveenriched mixtures 75:25 to give the title compound.

[0535] HPLC: column Chiralpack AD 25 cm×4.6 mm×5 μm, mobile phasen-hexane/EtOH 80:20, flow 7 ml/min; detector DAD, λ=220-360 nm, scanrange 150-1000; ionisation method ES/+; retention time 6.66 minutes(enantiomer 1; 26.4% a/a) and 8.82 minutes (enantiomer 2; 73.6% a/a).

EXAMPLE 5 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid,(3,5-dichloro-benzyl)-methylamide (enantiomer 1) (5a)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide (enantiomer 2) (5b)

[0536] The compound of Example 2a (500 mg) was separated by HPLC(conditions: column Chiralpack AD 25 cm×2mm, mobile phase n-hexane/EtOH80:20, flow 7 mL/min; detector DAD, λ=310 nm) into enantiomers. Thus,the title compound 5a (233 mg) and the title compound 5b (192 mg) wereobtained.

EXAMPLE 5a

[0537] HPLC-MS: column Phenomenex LUNA C18 15 cm×4.6 mm×5 μm, mobilephase buffer ammonium acetate 10 mM pH=6.8/acetonitrile from 70:30 to10:90 in 10 minutes, then 10:90 for 5 minutes; detector DAD, MS, ELSD,λ=220-360 nm; ionisation method ES/+, scan range 150-1000; retentiontime 11.94 minutes, m/z=410 [M+H]⁺.

EXAMPLE 5b

[0538] HPLC-MS: column Phenomenex LUNA C18 15 cm×4.6 mm×5 μm, mobilephase buffer ammonium acetate 10 mM pH=6.8/acetonitrile from 70:30 to10:90 in 10 minutes, then 10:90 for 5 minutes; detector DAD, MS, ELSD,λ=220-360 nm; ionisation method ES/+, scan range 150-1000; retentiontime 10.66 minutes, m/z=410 [M+H]⁺.

EXAMPLE 6a 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid[1-(3,5-dichloro-phenyl)-ethyl]-methylamide (diastereoisomer A

[0539] TFA (0.6 mL) was added to a solution of intermediate 8a (33 mg)in anhydrous DCM (3 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 5 hours, then it wasconcentrated in vacuo. The residue was diluted with AcOEt (10 mL) andwashed with a saturated sodium carbonate solution (3×5 mL) and brine (5mL). The organic layer was dried and concentrated in vacuo to a residuewhich was purified by flash chromatography (from DCM 100% to DCM/MeOH95:5) to give the title compound (10.7 mg) as a yellow wax.

[0540] T.l.c.: DCM/MeOH 9:1, Rf=0.57.

[0541] IR (nujol, cm⁻¹): 1629 (C═O).

[0542]¹H-NMR (d₆-DMSO—70° C.): δ (ppm) 7.39 (bs, 1H); 7.06 (dd, 1H);6.95 (bs, 2H); 7.0-6.8 (bm, 2H); 5.49 (bq, 1H); 4.09 (bd, 1H); 3.2-2.5(bm, 9H); 2.29 (s, 3H); 1.25 (bm, 3H).

[0543] MS (ES/+): m/z=424 [M+H]⁺.

EXAMPLE 6b 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid[1-(3,5-dichloro-phenyl)-ethyl]-methylamide (6b) (diastereoisomer B)

[0544] TFA (0.6 mL) was added to a solution of intermediate 8b (28 mg)in anhydrous DCM (3 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 5 hours, then it wasconcentrated in vacuo. The residue was diluted with AcOEt (10 mL) andwashed with a saturated sodium carbonate solution (3×5 mL) and brine (5mL). The organic layer was dried and concentrated in vacuo to a residuewhich was purified by flash chromatography (from DCM 100% to DCM/MeOH95:5) to give the title compound (16 mg) as a yellow wax.

[0545] T.l.c.: DCM/MeOH 9:1, Rf=0.50. IR (nujol, cm⁻¹): 1640 (C═O).

[0546]¹H-NMR (d₆-DMSO—70° C.): δ (ppm) 7.46 (t, 1H); 7.06 (dd, 1H); 6.99(dd, 1H); 6.88 (bs, 2H); 6.84 (dt, 1H); 5.56 (q, 1H); 4.17 (bd, 1H);3.2-3.0 (m, 2H); 3.0-2.8 (m, 3H); 2.6 (bm, 1H); 2.62 (s, 3H); 2.3 (s,3H); 1.3 (d, 3H).

[0547] MS (ES/+): m/z=424 [M+H]⁺.

EXAMPLE 7 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid[1-(3,5-dichloro-phenyl)-ethyl]-methylamide (7a) (diastereoisomer 1)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid[1-(3,5-dichloro-phenyl)-ethyl]-methylamide (7b) (diastereoisomer 2)

[0548] The compound of Example 6b (12 mg) was separated by HPLC(conditions: column Chiralpack AD 25 cm×2 mm, mobile phase n-hexane/EtOH80:20, flow 7 mL/min; detector DAD, λ=225 nm) into enantiomers. Thus,the title compound 7a (4 mg) and the title compound 7b (4.2 mg) wereobtained.

[0549] Compound 7a:

[0550] HPLC: column Chiralpack AD 25 cm×4.6 mm×5 μm, mobile phasen-hexane/EtOH 80:20; flux=1 mL/min; retention time 6.5 minutes.

[0551] Compound 7b:

[0552] HPLC: column Chiralpack AD 25 cm×4.6 mm×5 μm, mobile phasen-hexane/EtOH 80:20; flux=1 mL/min; retention time 7.9 minutes.

EXAMPLE 8 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5bis-trifluoromethyl-benzyl)-methylamide hydrochloride (enantiomer 1)

[0553] A mixture of intermediate 18 (54 mg) in EtOH (10 mL) containingglacial acetic acid (90 μL) and 10% palladium on carbon (18 g) wasstirred under hydrogen at 6 atmospheres for 3 hours. The mixture wasfiltered through a pad of celite, which was washed with further EtOH.Concentration in vacuo gave a crude which was purified by flashchromatography (DCM/MeOH 95:5) to give1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide (38 mg) as a yellow gum(T.l.c.: AcOEt/MeOH 8:2, Rf=0.18).

[0554] This material (38 mg) was dissolved in anhydrous Et2O (2 mL) andtreated at 0° C. with hydrochloric acid (1M in Et2O -87 μL). The mixturewas stirred at 0° C. for 30 minutes, then concentrated in vacuo. Theresidue was washed with pentane to give the title compound (11 mg) as awhitish solid.

[0555]¹H-NMR (d₆-DMSO-60° C.): δ (ppm) 9.0 (bs, 1H); 8.5 (bs, 1H); 7.97(s, 1H); 7.78 (s, 2H); 6.98 (dd, 1H); 6.92 (dd, 1H); 6.72 (dt, 1H); 4.78(d, 1H); 4.5 (t, 1H); 4.35 (d, 1H); 3.44-2.93 (m, 6H); 2.65 (s, 3H);2.29 (s, 3H).

[0556] SFC: column Chirapack AD 25 cm×4.6 mm, column temperature 35° C.,mobile phase CO2/EtOH (+0.15 isopropanol) 65:35, column pressure 180bar, flow 2.5 mL/min, detector UV-MS, λ=225 nm; retention time 2.72minutes (enantiomer 1); m/z=78 [M+H—HCl]⁺, 73% a/a).

EXAMPLE 9 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride (enantiomer2)

[0557] A mixture of intermediate 20 (90 mg) in EtOH (10 mL) containingglacial acetic acid (0.1 mL) and 10% palladium on carbon (30 g) wasstirred under hydrogen at 6 atmospheres for 3 hours. The mixture wasfiltered through a pad of celite, which was washed with further EtOH.Concentration in vacuo gave a crude which was purified by flashchromatography (DCM/MeOH 95:5) to give1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide (36 mg) as a yellow gumT.l.c.: AcOEt/MeOH 8:2, Rf=0.18).

[0558] This material (36 mg) was dissolved in anhydrous Et2O (2 mL) andtreated at 0° C. with hydrochloric acid (1M in Et2O—83 μL). The mixturewas stirred at 0° C. for 30 minutes, then concentrated in vacuo. Theresidue was washed with pentane to give the title compound (27 mg) as awhitish solid.

[0559]¹H-NMR (d₆-DMSO): δ (ppm) 9.19 (bs, 1H); 8.58 (bs, 1H); 7.97 (s,1H); 7.77 (s, 2H); 7.0-6.8 (m, 2H); 6.73 (dt, 1H); 4.78 (d, 1H); 4.54(t, 1H); 4.34 (d, 1H); 3.43 (bs, 3H); 3.4-3.15 (m, 3H); 2.94 (m, 1H);2.68 (s, 3H); 2.29 (s, 3H).

[0560] SFC: column Chirapack AD 25 cm×4.6 mm, column temperature 35° C.,mobile phase CO2/EtOH (+0.15 isopropanol) 65:35, column pressure 180bar; flow 2.5 mL/min, detector UV-MS, λ=225 nm; retention time 3.6minutes (enantiomer 2; m/z=478 [M+H—HCl]+, 79% a/a).

EXAMPLE 10 (±) 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dibromo-benzyl)-methylamide hydrochloride

[0561] TFA (1.72 mL) was dropped into a solution of intermediate 21 (316mg) in dry DCM (6.6 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 5 hours, thenconcentrated in vacuo. The residue was diluted with AcOEt and washedwith a saturated sodium hydrogen carbonate solution. The organic layerwas dried and concentrated in vacuo. The residue was purified by flashchromatography (DCM/MeOH 9:1) to give1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dibromo-benzyl)-methylamide (149.4 mg) as a colourless oil.

[0562] T.l.c.: DCM/MeOH 9:1, Rf=0.34.

[0563] This material (149.4 mg) was dissolved in anhydrous Et2O (3.3 mL)and treated at −10° C. with hydrochloric acid (1M in Et2O—0.36 mL). Themixture was stirred at −10° C. for 30 minutes, then concentrated invacuo. The residue was washed with pentane to give the title compound(141 mg) as a white solid.

[0564]¹H-NMR (d₆-DMSO): δ (ppm) 8.8 (bs, 2H); 7.73 (bs, 1H); 7.27 (bs,2H); 7.04 (dd, 1H); 6.99 (m, 1H); 6.88 (m, 1H); 4.7-4.0 (bm, 3H);3.5-2.8 (bm, 6H); 2.59 (s, 3H); 2.3 (s, 3H).

[0565] MS (ES/+): m/z=498 [M+H—HCl]⁺.

EXAMPLE 11 (±) 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,4-dibromo-benzyl)-methylamide hydrochloride

[0566] TFA (0.52 nm) was dropped into a solution of intermediate 22(94.1 mg) in dry DCM (2 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 5 hours, thenconcentrated in vacuo. The residue was diluted with AcOEt (2 mL) andwashed with a saturated sodium hydrogen carbonate solution. The organiclayer was dried and concentrated in vacuo. The reaction was notcomplete, thus the residue was dissolved in anhydrous DCM (1.3 mL),cooled to 0° C. under a Nitrogen atmosphere and treated with TFA (0.34mL). The solution was stirred at 0° C. for 5 hours, then concentrated invacuo. The residue was diluted with AcOEt (2 mL) and washed with asaturated sodium hydrogen carbonate solution. The organic layer wasdried and concentrated in vacuo. The residue was purified by flashchromatography (DCM/MeOH 9:1) to give1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,4-dibromo-benzyl)-methylamide (41.8 mg) as a colourless oil.

[0567] T.l.c.: DCM/MeOH 8:2, Rf=0.6.

[0568] This material (41.8 mg) was dissolved in anhydrous Et2O (0.92 mL)and treated at −10° C. with hydrochloric acid (1M in Et2O—0.1 mL). Themixture was stirred at −10° C. for 30 minutes, then concentrated invacuo. The residue was washed twice with pentane to give the titlecompound (10.5 mg) as a white solid.

[0569]¹H-NMR (d₆-DMSO): δ (ppm) 9.1-8.55 (2bs, 2H); 7.62 (d, 1H); 7.45(bs, 1H); 7.05 (dd, 1H); 6.99 (m, 1H); 6.87 (m, 2H); 4.7-4.0 (m, 3H);3.5-2.8 (bm, 6H); 2.56 (bs, 3H); 2.3 (s, 3H).

EXAMPLE 12 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dibromo-benzyl)-methylamide hydrochloride (12a—enantiomer 1)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3.5-dibromo-benzyl)-methylamide hydrochloride (12b—enantiomer 2)

[0570] The compound of EXAMPLE 10 (120 mg) was dissolved in a 5% sodiumhydrogen carbonate solution (10 mL) and extracted with AcOEt (15 mL).The organic layer was dried and concentrated in vacuo to give1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dibromo-benzyl)-methylamide (94 mg). This material was separatedinto enantiomers by HPLC (conditions: column Chiralcel OD 25 cm×20 mm,mobile phase n-hexane/EtOH 80:20, flow 7 mL/min; detector DAD, λ=225nm). Thus, 1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dibromo-benzyl)-methylamide was obtained as:

[0571] enantiomer 1 (36.4 mg): retention time 20.8 minutes

[0572] enantiomer 2 (37.8 mg): retention time 26 minutes.

EXAMPLE 12a

[0573] Enantiomer 1 (36.4 mg) was dissolved in anhydrous Et2O (1 mL) andtreated at −10° C. with hydrochloric acid (1M in Et2O—87.5 μL). Themixture was stirred at 0° C. for 15 minutes, then concentrated in vacuo.The residue was triturated with pentane (2×1 mL) to give the titlecompound 12a (26.2 mg) as a white solid.

[0574] HPLC-MS: column Chiralcel OD 25 cm×4.6 mm, mobile phasen-hexane/EtOH 80:20; flow 1 ml/min; detector DAD, λ=225 nm; retentiontime 7.3 minutes (100% a/a).

[0575] M.p.: 79-80° C. (dec).

[0576]¹H-NMR (d₆-DMSO—60° C.): δ (ppm) 9.3-8.62 (2s, 2H); 7.68 (s, 1H);7.26 (s, 2H); 7.0 (m, 2H); 6.87 (m, 1H); 4.6 (d, 1H); 4.54 (m, 1H); 4.15(d, 1H); 3.45-3.3 (m, 2H); 3.45-3.3 (m, 2H); 3.2-3.0 (m, 2H); 2.64 (s,3H); 2.31 (s, 3H).

EXAMPLE 12b

[0577] Enantiomer 2 (37.8 mg) was dissolved in anhydrous Et2O (1 mL) andtreated at 0° C. with hydrochloric acid (1M in Et2O—90.8 μL). Themixture was stirred at 0° C. for 15 minutes, then concentrated in vacuo.The residue was triturated with pentane (2×1 mL) to give the titlecompound 12b (28.1 mg) as a white solid.

[0578] HPLC-MS: column Chiralcel OD 25 cm×4.6 mm, mobile phasen-hexane/EtOH 80:20; flow 1 mL/min; detector DAD, λ=225 nm; retentiontime 8.9 minutes (100% a/a).

[0579] M.p.:79-80° C. (dec).

[0580]¹H-NMR (d₆-DMSO—70° C.): δ (ppm) 8.4-8.1 (bs, 2H); 7.68 (s, 1H);7.25 (s, 2H); 7.0 (m, 2H); 6.87 (m, 1H); 4.6-4.18 (2d, 2H); 4.44 (m,1H); 3.39 (m, 2H); 3.26 (m, 2H); 3.1-2.9 (m, 2H); 2.66 (s, 3H); 2.35 (s,3H).

EXAMPLE 13 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide(diastereoisomer 1)

[0581] TFA (0.5 mL) was added to a solution of intermediate 23a (12 mg)in anhydrous DCM (2 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 3 hours, then it wasconcentrated in vacuo. The residue was diluted with a saturated sodiumcarbonate solution and extracted twice with AcOEt. The organic layer wasdried and concentrated in vacuo to a residue which was purified by flashchromatography (DCM/MeOH 95:5) to give the title compound (5 mg) as acolourless oil.

[0582]¹H-NMR (d₆-DMSO—50° C.): δ (ppm) 7.8 (bs, 1H); 7.56 (bs, 2H); 6.93(bm, 1H); 6.86 (bd, 1H); 6.67 (bm, 1H); 5.99 (bq, 1H); 4.14 (t, 1H);3.62 (bm, 3H); 3.45-3.1 (m, 2H); 2.82 (bm, 1H); 2.42 (s, 3H); 2.33 (s,3H); 2.07 (s, 3H); 1.45 (bd, 3H).

[0583] MS (ES/+): m/z=492 [M+H]⁺.

EXAMPLE 14 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamidetrifluoroacetate (diastereoisomer 2)

[0584] TFA (1 mL) was added to a solution of intermediate 23b (12 mg) inanhydrous DCM (3 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 20 hours, then it wasconcentrated in vacuo. The residue was diluted with a saturated sodiumcarbonate solution and extracted twice with AcOEt The organic layer wasdried and concentrated in vacuo to a residue which was purified by flashchromatography (DCM/MeOH 95:5) to give the title compound (12 mg) as acolourless oil.

[0585]¹H-NMR (d₆-DMSO—50° C.): δ (ppm) 7.76 (bs, 1H); 7.51 (bs, 2H);7.09 (m, 1H); 6.9-6.8 (m, 2H); 5.94 (m, 1H); 4.03 (m, 1H); 3.4 (m, 1H);3.3 (m, 1H); 3.2 (m, 1H); 3.14 (m, 1H); 3.0 (m, 1H); 2.6 (m, 1H); 2.54(s, 3H); 2.35 (s, 3H); 1.35 (d, 3H).

[0586] MS (ES/+): m/z=492 [M+H]⁺.

EXAMPLE 15 (±) 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3-chloro-4-fluoro-benzyl)methylamide hydrochloride

[0587] TFA (1.25 mL) was added to a solution of intermediate 24 (43 mg)in anhydrous DCM (4 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 20 hours, then it wasconcentrated in vacuo. The residue wag diluted with a saturated sodiumcarbonate solution and extracted twice with AcOEt. The organic layer wasdried and concentrated in vacuo to a residue which was purified by flashchromatography (DCM/MeOH 95:5) to give1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3-chloro-4-fluoro-benzyl)methylamide (27 mg).

[0588] This material (27 mg) was dissolved in anhydrous Et2O (2 mL) andtreated at 0° C. with hydrochloric acid (1M in Et2O—82 μL). The mixturewas stirred at 0° C. for 30 minutes, then concentrated in vacuo. Theresidue was triturated with pentane to give the title compound (18.3 mg)as a white solid.

[0589]¹H-NMR (d₆-DMSO—70° C.): δ (ppm) 9.8-8.5 (b, 2H); 7.2 (m, 2H);7.01 (m, 2H); 6.86 (m, 1H); 4.58 (bd, 1H); 4.5 (bm, 1H); 4.14 (d, 1H);3.6-2.9 (m, 6H); 2.67 (s, 3H); 2.31 (s, 3H).

[0590] MS (ES/+): m/z=394 [M+H—HCl]⁺.

EXAMPLE 16 (±) 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(2,5-dichloro-benzyl)-methylamide hydrochloride

[0591] TFA (1.5 mL) was added to a solution of intermediate 25 (50 mg)in anhydrous DCM (5 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. overnight, then it wasconcentrated in vacuo. The residue was diluted with a saturated sodiumcarbonate solution and extracted twice with AcOEt. The organic layer wasdried and concentrated in vacuo to a residue which was purified by flashchromatography (DCM/MeOH 95:5) to give1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(2,5dichloro-benzyl)-methylamide (22 mg).

[0592] This material (22 mg) was dissolved in anhydrous Et2O (2 mL) andtreated at 0° C. with hydrochloric acid (1M in Et2O—64 μL). The mixturewas stirred at 0° C. for 30 minutes, then concentrated in vacuo. Theresidue was triturated with pentane to give the title compound (15 mg)as a white solid.

[0593]¹H-NMR (d₆-DMSO—70° C.): δ (ppm) 9.5-8.5 (b, 2H); 7.44 (m, 1H);7.34 (m, 1H); 7.11 (m, 2H); 7.02 (m, 1H); 6.92 (m, 1H); 4.62 (bm, 1H);4.6 (bd, 1H); 4.32 (d, 1H); 3.7-2.9 (m, 6H); 2.74 (bs, 3H); 2.33 (bs,3H).

[0594] MS (ES/+): m/z=410 M+H—HCl]⁺.

EXAMPLE 17 (±) 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3-fluoro-5-trifluoromethyl-benzyl)-methylamide hydrochloride

[0595] TFA (2.5 mL) was added to a solution of intermediate 27 (60 mg)in anhydrous DCM (15 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 4 hours, then it wasconcentrated in vacuo. The residue was diluted with a saturated sodiumhydrogen carbonate solution and extracted with AcOEt. The organic layerwas dried and concentrated in vacuo to a residue which was purified byflash chromatography (from DCM 100% to DCM/MeOH 9:1) to give1-(4-fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3-fluoro-5-trifluoromethyl-benzyl)-methylamide (33 mg). This material(33 mg) was dissolved in anhydrous Et2O (1 mL) and treated at 0° C. withhydrochloric acid (1M in Et2O -93 μL). The mixture was stirred at 0° C.for 30 minutes, then concentrated in vacuo. The residue was trituratedwith Et2O/pentane to give the title compound (12.7 mg) as a whitishsolid.

[0596]¹H-NMR (d₆-DMSO—70° C.): δ (ppm) 9.18 (bs, 1H); 8.62 (bs, 1H);7.49 (bd, 1H); 7.33 (bs, 1H); 7.02 (m, 2H); 6.81 (m, 2H); 4.68 (d, 1H);4.54 (m, 1H); 4.29 (d, 1H); 3.44 (m, 3H); 3.32 (m, 2H); 2.96 (m, 1H);2.69 (s, 3H); 2.31 (s, 3H).

[0597] MS (ES/+): m/z=428 [M+H—HCl]⁺.

EXAMPLE 18 (±) 1-(2,4-Difluoro-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide hydrochloride

[0598] TFA (1 mL) was dropped into a solution of intermediate 34 (93 mg)in anhydrous DCM (9 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. overnight, then it wasconcentrated in vacuo. The residue was diluted with AcOEt and washedwith a saturated potassium carbonate solution. The aqueous layer wasextracted with further AcOEt. The combined organic extracts were washedwith brine, dried and concentrated in vacuo to a residue which waspurified by flash chromatography (DCM/MeOH 95:5) to give1-(2,4difuoro-phenyl)-piperazine-2-carboxylic acid(3,5-dichlorobenzyl)-methylamide (42.8 mg).

[0599] This material (42 mg) was dissolved in anhydrous Et2O (1 mL) andtreated at −10° C. with hydrochloric acid (1M in Et2O—0.1 mL). Themixture was stirred at −10° C. for 30 minutes, then concentrated invacuo. The residue was triturated with pentane (3×2 mL) to give thetitle compound (38.9 mg) as a whitish solid.

[0600]¹H-NMR (d₆-DMSO—70° C.): δ (ppm) 9.19 (bs, 2H); 7.42 (s, 1H); 7.06(s, 2H); 7.17-6.92 (m, 3H); 4.81 (m, 1H); 4.7-4.18 (m, 2H); 3.56 (m,1H); 3.38 (m, 2H); 3.26 (m, 2H); 2.83 (m, 1H); 2.83 (s, 3H).

[0601] MS (ES/+): m/z=414 M+H—HCl]⁺.

EXAMPLE 19 (±) 1-(2,4-Difluoro-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride

[0602] TFA (1 mL) was dropped into a solution of intermediate 35 (115mg) in anhydrous DCM (9 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. overnight, then it wasconcentrated in vacuo. The residue was diluted with AcOEt and washedwith a saturated potassium carbonate solution. The aqueous layer wasextracted with further AcOEt. The combined organic extracts were washedwith brine, dried and concentrated in vacuo to a residue which waspurified by flash chromatography (DCM/MeOH 95:5) to give1-(2,4-difluoro-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide (46 mg).

[0603] This material (46 mg) was dissolved in anhydrous Et2O (1 mL) andtreated at −10° C. with hydrochloric acid (1M in Et2O—0.1 mL). Themixture was stirred at −10° C. for 30 minutes, then concentrated invacuo. The residue was triturated with pentane (3×2 mL) to give thetitle compound (45 mg) as a whitish solid.

[0604]¹H-NMR (d₆-DMSO—70° C.): δ (ppm) 10-8.4 (2bs, 2H); 7.93 (s, 1H);7.76 (s, 2H); 7.2-6.84 (m, 3H); 4.84 (m, 1H); 4.7-4.3 (dd, 2H); 3.6-3.0(m, 6H); 2.86 (s, 3H).

[0605] MS (ES/+): m/z=482 [M+H—HCl]⁺.

EXAMPLE 20 (±) 1-(2,4,6-Trifluoro-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide hydrochloride

[0606] TFA (0.5 mL) was dropped into a solution of intermediate 42 (25mg) in anhydrous DCM (4 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. overnight, then it wasconcentrated in vacuo. The residue was diluted with AcOEt and washedwith a saturated potassium carbonate solution. The aqueous layer wasextracted with further AcOEt. The combined organic extracts were washedwith brine, dried and concentrated in vacuo to a residue which waspurified by flash chromatography (DCM/MeOH 9:1) to give1-(2,4,6-trifluoro-phenyl)-piperazine-2-carboxylic acid(3,5-dichlorobenzyl)-methylamide (10.3 mg).

[0607] This material (10.3 mg) was dissolved in anhydrous Et2O (0.8 mL)and treated at −10° C. with hydrochloric acid (1M in Et2O—30 μL). Themixture was stirred at −10° C. for 15 minutes, then concentrated invacuo. The residue was triturated with pentane (3×2 mL) to give thetitle compound (11.9 mg) as a whitish solid.

[0608]¹H-NMR (d₆-DMSO—70° C.): δ (ppm) 9.3-8.4 (2bs, 2H); 7.45 (s, 1H);7.2 (s, 2H); 7.0 (s, 2H); 4.72 (bm, 1H); 4.65 (d, 1H); 4.21 (d, 1H);3.5-3.3 (m, 6H); 2.86 (s, 3H).

[0609] MS (ES/+): m/z=432 [M+H—HCl]⁺.

EXAMPLE 21 (±) 1-(2,4,6-Trifluoro-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride

[0610] TFA (0.5 mL) was dropped into a solution of intermediate 43 (31mg) in anhydrous DCM (5 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. overnight, then for TFA(0.2 mL) was added and the solution was stirred at 0° C. for further 2hours. The solution was concentrated in vacuo. The residue was dilutedwith AcOEt and washed with a saturated potassium carbonate solution. Theaqueous layer was extracted with further AcOEt. The combined organicextracts were washed with brine, dried and concentrated in vacuo to aresidue which was purified by flash chromatography (DCM/MeOH 98:2) togive 1-(2,4,-trifluoro-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide (18.1 mg).

[0611] This material (18.1 mg) was dissolved in anhydrous Et2O (1 mL)and treated at −10° C. with hydrochloric acid (1M in Et2O—0.08 mL). Themixture was stirred at −10° C. for 15 minutes, then concentrated invacuo. The residue was triturated with pentane to give the titlecompound (10 mg) as a whitish solid.

[0612]¹H-NMR (d₆-DMSO—70° C.): δ (ppm) 8.6-8.3 (2bs, 2H); 7.94 (s, 1H);7.78 (s, 2H); 6.95 (t, 2H); 4.84 (bd, 1H); 4.67 (bt, 2H); 4.4 (bd, 1H);3.5-3.1 (m, 6H); 2.86 (s, 3H).

[0613] MS (ES/+): m/z=500 [M+H—HCl)⁺.

EXAMPLE 22 (±) 1-(4-Fluoro-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride

[0614] A mixture of intermediate 47 (77 mg) in EtOH (10 mL) containing 2drops of glacial acetic acid and 10% palladium on carbon (20 mg) wasstirred under hydrogen at 6 atmospheres for 22 hours. The mixture wasfiltered through a pad of celite. Concentration in vacuo gave a crudewhich was purified by flash chromatography (AcOEt/MeOH 9:1) to give1-(4-fluoro-phenyl)-piperazine-2-carboxylic acid,(3,5-bis-trifluoromethyl-benzyl)-methylamide (44 mg). This material (44mg) was dissolved in anhydrous Et2O (3 mL) and treated at 0° C. withhydrochloric acid (1M in Et2O—114 μL). The mixture was stirred at 0° C.for 15 minutes, then concentrated in vacuo. The residue was trituratedwith pentane to give the title compound (35 mg) as a whitish solid.

[0615]¹H-NMR (d₆-DMSO): δ (ppm) 9.6-9.4 (bs, 1H); 8.4-8.2 (bs, 1H); 8.02(s, 1H); 7.79-7.62 (2s, 1H); 7.05-6.8 (m+dd, 2H); 5.27 (2s, 1H);4.91-4.64 (2d, 1H); 4.64-4.41 (2d, 1H); 3.6-3.06 (m, 6H); 2.94-2.85 (2s,3H).

[0616] MS (ES/+): m/z=464 [M-HCl+H]⁺.

EXAMPLE 23 (±) 1-(4-Fluoro-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide hydrochloride

[0617] TFA (2 mL) was dropped into a solution of intermediate 51 (65 mg)in anhydrous DCM (10 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. overnight, then it wasconcentrated in vacuo. The residue was diluted with AcOEt and washedwith a saturated sodium carbonate solution. The aqueous layer wasextracted with further AcOEt. The combined organic extracts were washedwith brine, dried and concentrated in vacuo to a residue which waspurified by flash chromatography (DCM/MeOH 9:1) to give1-(4-fluoro-phenyl)-piperazine-2-carboxylic acid(3,5-dichlorobenzyl)-methylamide (15 mg). This material (15 mg) wasdissolved in anhydrous Et2O (1 mL) and treated at 0° C. withhydrochloric acid (1M in Et2O—42 μL). The mixture was stirred at 0° C.for 15 minutes, then concentrated in vacuo. The residue was trituratedwith pentane to give the title compound (11.9 mg) as a whitish solid.

[0618]¹H-NMR (d₆-DMSO): δ ppm) 9.42 (bs, 1H); 8.25 (bs, 1H); 7.48 (s,1H); 7.15-6.8 (m, 6H); 5.14 (m, 1H); 4.68 (d, 1H); 4.26 (d, 1H); 3.6-3.0(m, 6H); 2.87 (s, 3H);

[0619] MS (ES/+): m/z=396 [M+H—HCl]⁺.

EXAMPLE 24 (±) 1-(4-Trifluoro-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide hydrochloride

[0620] TFA (1 mL) was dropped into a solution of intermediate 58 (60 mg)in anhydrous DCM (4.5 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 16 hours, then it wasdiluted with a saturated sodium carbonate solution and extracted twicewith AcOEt. The combined organic extracts were dried and concentrated invacuo to a residue which was purified by flash chromatography (DCM/MeOH9:1) to give 1-4-trifluoromethyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichlorobenzyl)-methylamide (45 mg—T.l.c.: DCM/MeOH 9:1, Rf=0.34).

[0621] This material (45 mg) was dissolved in anhydrous Et2O (1 mL) andAcOEt (2 mL) and treated at −5° C. with hydrochloric acid (1M inEt2O—110 μL). The mixture was stirred at 0° C. for 30 minutes, thenconcentrated in vacuo. The residue was triturated with pentane to givethe title compound (25.1 mg).

[0622]¹H-NMR (d₆-DMSO): δ (ppm) 9.82 (bs, 1H); 8.32 (bs, 1H); 7.7-6.9(m+m, 7H); 5.44 (s, 1H); 4.73 (d, 1H); 4.32 (d, 1H); 4.14-3.0 (m, 6H);2.99-2.83 (s+s, 3H).

[0623] MS (ES/+): m/z=445 [M+H—HCl]⁺.

EXAMPLE 25 (±) 1-(4-Trifluoromethyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride

[0624] TFA (1 mL) was dropped into a solution of intermediate 59 (70 mg)in anhydrous DCM (4.5 mL) previously cooled to 0° C. under a Nitrogenatmosphere. The solution was stirred at 0° C. for 16 hours, then it wasdiluted with a saturated sodium carbonate solution and extracted twicewith AcOEt. The combined organic extracts were dried and concentrated invacuo to a residue which was purified by flash chromatography (DCM/MeOH9:1) to give 1-(4-trifluoromethyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethybenzyl)-methylamide (54 mg—T.l.c.: DCM/MeOH 9:1,Rf=0.39).

[0625] This material (54 mg) was dissolved in anhydrous Et2O (1.6 mL)and treated at −5° C. with hydrochloric acid (1M in Et2O—115 μL). Themixture was stirred at 0° C. for 30 minutes, then concentrated in vacuo.The residue was triturated with pentane to give the title compound (36mg).

[0626]¹H-NMR (d₆-DMSO): δ (ppm) 9.7 (bs, 1H); 8.3 (bs, 1H); 7.99-7.95(s+s, 1H); 7.81-7.55 (s +s, 2H); 7.54-7.37 (d+d, 2H); 7.13-6.85 (d+d,2H); 5.44-5.52 (s+s, 1H); 4.97-4.73 (d+d, 1H); 4.61-4.41 (d+d, 1H);3.9-3.0 (m, 6H); 3.03-2.92 (s+s, 3H).

[0627] MS (ES/+): m/z=513 [M+H—HCl]⁺.

EXAMPLE 26 (±) 1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylicacid, (3,5-dichloro-benzyl)-methylamide as a Crystalline form

[0628] Example 2a (1 g) was suspended in MeOH (12 mL) and heated to65-70° C. until completed dissolution. The mixture was cooled to 50° C.then it was filtered and concentrated to 10 mL. The resulting solutionwas cooled again to 20° C. and 0.005 g of example 2a seed was added. Thesolution was stirred over two hours before the slow (1 hour) addition ofwater (7.5 mL). The solid was stirred at 20° C. for 16-18 hours. Thefollowing day the solid was filtered and washed with MeOH/H2O 6/4 (3mL). It was dried in vacuum at 40° C. for 18 hours to obtain the titlecompound (0.9 g); mp 169.97° C.

[0629] X ray powder diffraction data are reported in table 1 TABLE 1 TheX-ray powder diffraction pattern of the product of Example 26 in termsof ‘d’ spacings is as follows Angle (°2θ) d value (A) 14,688 6,02618,744 4,730 20,812 4,285 21,691 4.094 25,034 3,554 25,687 3,465 25,9333,433 28,072 3,176

PHARMACY EXAMPLES

[0630] A. Capsules/Tablets Active ingredient  25.0 mg PYP  2.5 mgMicrocrystalline Cellulose 198.5 mg Croscarmellose Sodium  2.5 mgMagnesium Stearate  1.5 mg

[0631] The active ingredient is blended with the other excipients. Theblend can be used to fill gelatin capsules or compressed to form tabletsusing appropriate punches. The tablets can be coated using conventionaltechniques and coatings.

[0632] B. Tablets Active ingredient  25.0 mg Microcrystalline Cellulose264.0 mg Croscarmellose Sodium  10.0 mg Magnesium Stearate  1.0 mg

[0633] The active ingredient is blended with microcrystalline celluloseand croscarmellose sodium. Magnesium stearate is then added to thepreviuos blend. The mixture thus obtained can be compressed usingappropriate punches and the tablets coated using conventional techniquesand coatings.

[0634] C) Infusion Active ingredient 2-50 mg/ml Buffer solution pH 4.5suitable for infusion qs to 100 ml (e.g. sodium citrate in NaCl 0.9% or5% dextrose)

[0635] The formulation may be packed in glass vials or plastic bag.

[0636] The affinity of the compound of the invention for NK₁ receptorwas determined using the NK₁ receptor binding affinity method measuringin vitro by the compounds' ability to displace [3H]—substance P (SP)from recombinant human NK₁ receptors expressed in Chinese Hamster Ovary(CHO) cell membranes. The affinity values are expressed as negativelogarithm of the inhibition constant (Ki) of displacer ligands (pKi).

[0637] The pKi values obtained as the average of at least twodeterminations with representative compounds of the invention are withinthe range of 9.40 to 8.00.

[0638] The affinity of the compound of the invention for serotonintransporter was determined using the hSERT binding affinity method andmeasuring in vitro the compounds' ability to displace [3H]—Imipraminefrom recombinant human serotonin transporter expressed in HumanEmbryonic Kidney HEK293 cell membranes. The affinity values areexpressed as negative logarithm of the inhibition constant (Ki) ofdisplacer ligands (pKi).

[0639] The pKi values obtained as the average of at least twodeterminations with representative compounds of the invention are withinthe range of 6.31 to 8.95.

1. A compound of formula (I)

wherein R represents halogen, C₁₋₄ alkyl, trifluoromethoxy ortrifluoromethyl; R₁ is trifluoromethyl, C₁₋₄ alkyl, C₁₋₄ alkoxy, halogenor trifluoromethoxy; R₂ is hydrogen, C₁₋₄ alkyl or C₂₋₆ alkenyl; R₃represents hydrogen or C₁₋₄ alkyl; n and m are independently 0 or aninteger from 1 to 3; or a pharmaceutically acceptable salt or solvatethereof.
 2. A compound as claimed in claim 1 wherein R₁ istrifluoromethyl or halogen and n is
 2. 3. A compound as claimed in claim1 wherein R is selected from trifluromethyl, methyl or halogen, (e.gfluorine), R₁ is trifluoromethyl or halogen and n is 2, R₃ is methyl, R₂is methyl or hydrogen.
 4. A compound selected from(±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide;(+)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide;(−)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide; and amorphous and crystalline formsthereof and pharmaceutically acceptable salts thereof.
 5. A compoundselected from: (±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylicacid, (3,5-bis-trifluoromethyl-benzyl)-methylamide;(±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide;(±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid[1-(3,5-dichloro-phenyl)-ethyl]-methylamide;(±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-(±methylamide;(±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide;(±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,4-dibromo-benzyl)-methylamide;(±)1-(4-Trifluoromethyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide; and pharmaceuticallyacceptable salts and solvates thereof. 6-10. (Canceled)
 11. Apharmaceutical composition comprising a compound as claimed in claim 1in admixture with one or more pharmaceutically acceptable carriers orexcipients.
 12. A process for the preparation of a compound as claimedin claim 1, which comprises reacting an activated derivative of thecarboxylic acid of formula (II) or an enantiomer thereof, with amine(III),

wherein R_(a) is a suitable nitrogen protecting group; followed wherenecessary or desired by one or more of the following steps
 1. removal ofany protecting group;
 2. isolation of the compound as a salt or asolvate thereof;
 3. separation of a compound of formula(I) or derivativethereof into the enantiomers thereof. 13-14. (Canceled)
 15. A method forthe treatment of a condition mediated by tachykinins or selectiveinhibition of the serotonin reuptake transporter protein in a mammal inneed thereof, said method comprising administering an effective amountof a compound as claimed in claim
 1. 16. The method according to claim15, wherein said tachykinins are substance P or other neurokinins. 17.The method according to claim 15, wherein said mammal is man.
 18. Themethod according to claim 15, wherein said conditions are mediated byboth tachykinins and selective inhibition of the serotonin reuptaketransporter protein
 19. A method for the treatment of depression in amammal in need thereof, said method comprising administering aneffective amount of a compound as claimed in claim
 1. 20. The methodaccording to claim 19, wherein said mammal is man.
 21. A method for thetreatment of anxiety in a mammal in need thereof, said method comprisingadministering an effective amount of a compound as claimed in claim 1.22. The method according to claim 21, wherein said mammal is man.
 23. Amethod for the treatment of both depression and anxiety in a mammal inneed thereof, said method comprising administering an effective amountof a compound as claimed in claim
 1. 24. The method according to claim23, wherein said mammal is man.
 25. A compound selected from(±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide hydrochloride;(+)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide hydrochloride; and(−)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide hydrochloride.
 26. A compound selectedfrom: (±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid,(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride;(±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-methylamide hydrochloride;(±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid[1-(3,5-dichloro-phenyl)-ethyl]-methylamide hydrochloride;(±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-dichloro-benzyl)-(±methylamide) hydrochloride;(±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride;(±)1-(4-Fluoro-2-methyl-phenyl)-piperazine-2-carboxylic acid(3,4-dibromo-benzyl)-methylamide hydrochloride; and(±)1-(4-Trifluoromethyl-phenyl)-piperazine-2-carboxylic acid(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride.